# My Journal to DIY PVC Overflow for non-drilled tank to sump filtration design



## Captured Moments

This is my first journal and since I don't have a lot of free time, I will update and show steps every little bit at a time.

Topic covering: 
Complete contruction build of a DIY PVC Overflow system including the drain side and the return from the sump to the main display tank
Building a DIY wet/dry filtration system in the sump using a "rubbermaid" 4 drawer cart storage unit
Safety system using a Pump Stopper Kit from Aquahub to prevent display tank overflow

Quick Specs:
Main Display Tank - 135 gallon (55 in. Length x 24 in. Width x 26 in. Height), not drilled
Sump - Standard 90 gal. tank (4 ft. x 1.5 ft. deep x 2 ft. high) with no baffles or partitions
Return Pump: Quiet One 4000 (effectively pumps 650 gal per hr at 5 feet of head pressure (distance from outlet of pump to top of return)
Filtration: Wet/Dry system in the sump using a storage cart with drawers
Livestock: 18 in. Pacu and one 12 in. Mono Peacock Bass

The display tank:
I bought the main display tank of some member on BCA quite a few months back and it needed some TLC. It was within my budget at $75 and it has thick glass and the glass is in good shape with no scratches. It had wood cedar trim throughout on all edges and the wood needed additional moisture protection. I bought a can of marine varnish (Epifanes), sanded the wood clean, stained to a teak colour and applied about 6 coats of varnish. A tank of that size is pretty heavy and awkward to move by oneself but somehow I managed to tip the tank to the sides and bottom up and back and so on to apply the varnish and let dry and turn again.. etc.. That took a while to do. It's not furniture quality and super smooth (that would have entailed sanding between each coat) but finally I am happy enough with the result and hopefully it will last many years. To a suggestion by Gordon (GKlaw), I also applied a bead of silicone to the underside of the wood trim along the edges on the inner side of the tank to prevent water from seeping in between the wood trim and the glass.

The Overflow:
A while back I started researching on sump designs for freshwater setups, wet/dry filter designs, overflow boxes commonly available or having the tank drilled. I wanted to move away from Aquaclear 110 and canister filters. I wasn't happy with the overflow boxes and I didn't want to have my tank drilled. While doing my research I stumbled across a sticky on the "Monsterfishkeepers" website and they have a design plus lengthy discussion on the DIY PVC overflow that one can build.
Here is the basic template of the design of the overflow courtesy of Monsterfishkeepers and the sticky thread by Chompers.










After I made the commitment to the design, I started sketching out the entire system on paper and figuring out every pieces of PVC I needed to buy. From a flow rate handling capability standpoint it was also necessary to decide on the size of the PVC given the flow rate of my return pump. I went with 1.25 in. size PVC rather than 1 in. to give me ample flow surplus handling capability in case I decide later to upgrade to a larger return pump. Besides I don't believe the 1" size would even be satisfactory according to the chart below and would not provide any safety margin.
Here's an excerpt copy and paste again courtesy of Chompers at Monsterfishkeepers to help size PVC pipes.



> Cross Sectional Area (in square inches) - Pipe sizes vs. their cross sectional area. Useful for dividing flow between pipes.
> size __area
> 1/2 = .1963
> 3/4 = .4418
> 1.0 = .7854
> 1.25= 1.227
> 1.5 = 1.767
> 2.0 = 3.142
> 
> Maximum Gravitational Vertical Flow - This is what we look for when sizing drains or DIY overflows. The flow under the power of gravity reaches a maximum in the same way an object reaches Terminal Velocity as it falls through the air. The gravitational force is countered by the waters viscosity (resistance to flow) and the frictional resistance of the pipe. The viscosity creates a minimum vertical length to acheive the maximum flow. If the vertical pipe length is less than the minimum, the flow rate will be somewhat less than the pipes maximum potential.
> size _GPM __GPH
> 1/2 = 2.50 = 150
> 3/4 = 5.63 = 337.5
> 1.0 = 10.0 = 600
> 1.25=15.6 = 937.5
> 1.5 = 22.5 = 1350
> 2.0 = 40.0 = 2400
> 
> Min. Vertical Length
> 1/2 = 2"
> 3/4 = 5"
> 1.0 = 9"
> 1.25= 14"
> 1.5 = 20"
> 2.0 = 36"


So for example in my case, my return pump flows 650 gal./hr at 5 ft. of head. The total volume of water in the system is roughly 165 gallons (135 gal. from the main tank + 30 gal. in the sump). The turnover rate of the water being cycled in the entire system is thus 650/165 = 3.94 times every hour.
Using the reference above for gravitational vertical flow, using 1.25 PVC will handle a flow rate of 937 gph assuming you have a vertical down pipe of at least 14". That is enough safety margin for my pump effective output at 650 gph.

I ordered all the PVC parts from this website PVC Fittings Direct, PVC Fittings Schedule 40, Buy PVC Couplings, Adapters, Elbows, Tees, Caps & Plugs Online. Basically you would be needing Schedule 40 PVC fittings. The site is easy to navigate and figure out. Ordering was easy and the parts arrived about a week later.








- PVC Union Fitting, Fipt x Fipt (threaded on both ends). 







- PVC Ball Valve, Fipt x Fipt (threaded on both ends)

While I won't be listing all the PVC parts that I ordered and needing for the build, I will describe some aspects of the build later on with pictures. One note worth mentioning at this point is that union fittings and PVC ball valves are the most expensive components compared to all the other PVC components such as 90 deg. elbows, cap, nipples, adapters, T-fittings. For the build I needed 2 unions. One 1 1/4 in. union for the drain side and another 1 in. union for the return side. 
Price of the union fitting is: $10.10 for the 1 in. size and $15.38 for the 1 1/4 in. size
Price of the PVC ball valve is: $12.06 for 1 1/4 in. size and $14.87 for 1 1/2 in. size
You can get these in the "slip" type or the threaded type but because of the cost I decided to use the threaded (Fipt) type. Using the slip type would entail using glue and that is permanent. For reusability and upgrade later in future projects, you can dismantle a threaded type without wasting it.

Also high on the cost were the "Christy's Red Hot Blue Glue" PVC pipe cement 1/2 pint which was on sale for $14.95 and the "Christy's Ultra Seal Pipe Thread Sealant 1/2 pint which was $19.95 (not on sale). 
















There were a few extra PVC parts that I ordered to account for some slight build variations during construction.. sometimes things don't always go according to plan. Needless to say, the total cost of all the parts came to $155


----------



## Fansons

If I do it, my wife will kill me... Too many pipes, she doesn't like it.

But, looks cool!


----------



## Captured Moments

Here's my research sketch for the build. Sorry it's not to scale and I am not an artist but it helps to visualize.


----------



## AWW

Hey, Not sure how much you know about this, but i am gathering some information and was wondering if you could help.

I am trying to install a HOB overflow that can handle 3,000 gallons per hour. The largest one i have found for retail (I ordered it) Only handles 1,600 gallons per hour. Now, the simple solution would be to add two of these suckers and call it a day, But that really affects the bracing on my tank. 

So, here is what i am wondering. 

The bracing, as well as the width of the acrylic on my 450 gallon tank is 6". Can you make a PVC overflow that will go that far? I am trying to get away from removing any acrylic what so ever. Also, what do you figure the best width of PVC is? I know i am going to need to run more than one over flow.

Any help would be great,

Thanks,

Alex


----------



## gklaw

Hi Christian: 

Very nice planning  My brain is hurting trying to figure out how this thing would start siphoning and how it could restart after a power failure. Like to see that in action when I come over Monday 

Like what I was taught in elementary long long time ago: never too late to learn something new.


----------



## Captured Moments

Fansons said:


> If I do it, my wife will kill me... Too many pipes, she doesn't like it.
> 
> But, looks cool!


Then I am lucky because my wife will let me do almost anything regarding my aquarium hobby. She likes looking at my planted tanks although they could look better if I spend more time on them.


----------



## Captured Moments

AWW said:


> Hey, Not sure how much you know about this, but i am gathering some information and was wondering if you could help.
> 
> I am trying to install a HOB overflow that can handle 3,000 gallons per hour. The largest one i have found for retail (I ordered it) Only handles 1,600 gallons per hour. Now, the simple solution would be to add two of these suckers and call it a day, But that really affects the bracing on my tank.
> 
> So, here is what i am wondering.
> 
> The bracing, as well as the width of the acrylic on my 450 gallon tank is 6". Can you make a PVC overflow that will go that far? I am trying to get away from removing any acrylic what so ever. Also, what do you figure the best width of PVC is? I know i am going to need to run more than one over flow.
> 
> Any help would be great,
> 
> Thanks,
> 
> Alex


I am envious of your 450 gal. tank.  Maybe I will get something that size in the future.
I am not experienced and an expert on this PVC overflow but I learned a lot during my research and observing my system running steady for at least a couple of weeks now with the livestock. Prior to that I run tests for a week.
For the U-bend going over the top of your tank (bracing and width of acrylic at 6"), I don't think there is any problem with that distance. On mine using 1.25 in. PVC, it is already 3 inches. In your case you will need to use larger size PVC to handle your much higher flow rate requirement. At 2 in. PVC., you will probably find that distance to be close to 5". How this PVC overflow system works is not dependent on this distance. You might observe slightly lower flow rate capability if this distance were upward of 1 ft. or something like that but I don't believe this distance is of concern.
Most likely you will need to run 2 overflows. I don't suggest you use PVC larger than 2 in. because the price difference is quite big after that.
Maybe you can build one overflow using 2" PVC and the second overflow using 1.5" PVC. The 2" overflow will be your main overflow and the water intake level will be placed about 1/2 inch lower than the second smaller overflow. Why lower? because your primary overflow will take in most of the water and will be full and be mostly silent. The secondary smaller overflow will take the rest of the flow but will not have to work so hard and stay quieter without having to result to being full.
Hope this makes sense.


----------



## Captured Moments

gklaw said:


> Hi Christian:
> 
> Very nice planning  My brain is hurting trying to figure out how this thing would start siphoning and how it could restart after a power failure. Like to see that in action when I come over Monday
> 
> Like what I was taught in elementary long long time ago: never too late to learn something new.


Hey Gordon,
For sure I will show you when you come over. I'll show you my marijuana grow-op as well...:bigsmile: jk.
During the testing phase I simulated many power outages by stopping the pump. Since my return extends quite far down the water level in the main tank, I drilled a couple of "siphon break" holes about 1 in. below the water level, so in the vent of a power outage the siphon effect of the water from the display tank flowing back into the sump via the return line will be broken.
The PVC overflow system retains the prime even during a power outage. I already went through a real power outage for a few hours last week while I was at work. The entire system resumes itself once power comes back on.
At the top of the bend going over the tank, there is a Hagen Elite check valve. The check valve is used to prime the system and purge all the air off. The bottom 2 "u-bends" and the top bend is always full of water even when it is not running. The water level inside the bottom 2 "u-bends" is dictated by the height of the "T-Fitting" (F on the first diagram) because that is when the water will start actually overflowing into the sump.


----------



## Captured Moments

I regret not having taken some pictures during the actual build of the overflow system but I will try to cover every aspects with pictures. Here's a representation schematics of my overflow. The black outline is the complete overflow and I have placed some pictures in the areas to show the actual parts.


----------



## gklaw

I think I got it now - ingenious


----------



## Captured Moments

Starting with the intake in the tank, I decided to use a T-Fitting rather than a 90 deg. elbow or simply an upright PVC. Using a "T" would allow 2 points of entry rather than one. It is still one inlet but the water can rush in from both sides. The safety feature is that it can continue to function even if one of the entry point is plugged by god knows what. The coupling, the short PVC pipe and the "T" fitting are purposely not glued together. This allows me to fine tune the water level in the main display tank. I can raise or lower the intake accordingly by pressing the parts in more or by pulling them apart. I can also change the length of that short connecting pipe. Even if this part were to leak slightly or in a worst case scenario to come apart, it would be of no real concern as the water level can drop to the bottom of the last connecting segment (the coupling) and the sump would still be able to handle the extra water volume without overflowing.

The bottom loop inside the tank is straightforward and the parts are glued together. For simplicity and for how the overflow functions, it is best to keep the 2 bottom loops at the same level (the bottom loop inside the tank and the bottom loop outside the tank).


----------



## gklaw

AWW said:


> I am trying to install a HOB overflow that can handle 3,000 gallons per hour. The largest one i have found for retail (I ordered it) Only handles 1,600 gallons per hour. Now, the simple solution would be to add two of these suckers and call it a day, But that really affects the bracing on my tank.


The principle should work whether it is 1/2" or 2". I think the problem lies in the top bend when the air will tend to trap. I the air lifter can keep up with pulling the air out. Make one out of a 2" pipe to see if that work. You don't even need to buy the valve yet. If it works cut the valve in later. PVC pipe is cheap.

Alex:

I am also surprise that you would rely on siphon that drilling a couple of hole at the back of the tank for overflow. At 3,000 gph, any hiccup with the sipphon and you will have a deluge


----------



## Captured Moments

Next is the top loop portion of the overflow. The top loop is always full of water even when the unit is stopped and the return pump is not pumping water back into the display tank. A small hole is drilled at the top of one of the PVC elbow and a check valve is placed there. I used silicone to hold the check valve in place. The check valve is used to prime the system and to remove trapped air bubbles.
For the construction, you can basically glue the 2 elbows with a short connecting piece of PVC pipe.
























In my case I did not glue the 2 elbows permanently because I wanted to be able to dismantle the unit if needed. During my research I read some people comment about how over time gunk will build up inside the overflow and thus restrict flow and potentially can trap more air in the process. I had to think of a way to split apart the entire unit for cleaning. 
Instead of gluing the 2 elbows together, I used a fitting with a thread on one end and a "spig" on the other. The spig is basically like a pipe and the same diameter as a pipe. The spig can connect directly to another fitting without having to use a piece of PVC pipe. In the picture, one of the 90 deg. elbow has a FIPT thread on one end and a Slip joint on the other end. Apply pipe thread sealant and screw the threaded male MIPT end of the adapter to the threaded FIPT end of the elbow. For the other side, it is just glued. 
You can also use a regular male adapter (MIPT thread on one end and slip joint on the other end) but you will need to use a short piece of PVC pipe to glue the other end.

























Here's a schematic when the unit is stopped. The blue part is the water. The 2 bottom loops prevent air from getting into the top loop and break siphon. The water level inside the 2 bottom loops is measured by the height of the T-fitting. You don't want to place the T-fitting too high because you will loose on flow rate capacity. For maximum flow, it is best to place the T-fitting as low as possible but not too low or you risk air getting past the bottom loop and break siphon. With running water, there is a fair amount of turbulence so keep a safety margin. The 2 bottom loops extend almost to the bottom of the aquarium to maximize the distance between the top of the water intake to the bottom of the T-fitting. This is to achieve maximum flow capacity. From my research, it was mentioned that the tubes should extend past at least half the depth of the aquarium.










When first setting up and to prime the entire system. Close the ball valve and pour water through the vent tube to fill the bottom loop and part of the vent tube. Pour water also from the intake side if needed depending on your current water level in the tank to fill the other bottom loop. With both bottom loops filled with water, put a piece of airline tubing to the check valve and connect to an air lifter pump or you can simply suck on the hose to pull air out and fill the top loop with water. With the system primed, open the ball valve and turn on the pump.

Here's a schematic when the unit is running. The dark blue shading represent the water movement throughout the overflow.


----------



## Captured Moments

Next is the rest of the overflow system which hangs outside the aquarium. It consists of a bottom loop, a T-fitting handling the actual "overflow", a rising vent tube and the rest of the components leading to the sump below.

















All the pieces are glued together to the exception of the PVC ball valve and the Union fitting which consist of a threaded connection. Again because of the cost of these components I opted to use threaded fittings rather than the glued slip type in the event that I needed to reuse these parts on future upgrades. I didn't want the ball valve to be restrictive in flow so I opted to use one size larger (1 1/2 in.) hence the reducing male adapters on both ends of the ball valve. The rest of the system is built on 1 1/4 in. size. The union fitting is optional but it makes it possible and convenient to disconnect at this point for ease of servicing and cleaning. This is convenient especially if the overflow is placed close to a wall or in a tight area.
I plumbed the entire drain side using solid piping but you could use flexible hose as an option. For example you can adapt a hose barb fitting after the ball valve or after the union fitting or after the 90 degree elbow and run a hose the rest of the way to the sump.

















Finally the overflow drain ends in an elbow followed by a very short piece of pvc pipe entering the top storage drawer compartment where the filtration begins. More on that later.


----------



## plantbrain

This design is the same as the Mame Japanese overflow, but cost 40X less.


----------



## neven

Tom, it seems a bit different than the mame style, i got one going myself and although similar, i find a mame much more compact. From the looks of it, rather than use the return to create the vaccuum to restart the siphon, it uses a pump (or venturi from the pump) Both works, but a mame eliminates the need for one airline


----------



## AWW

Captured Moments said:


> I am envious of your 450 gal. tank.  Maybe I will get something that size in the future.
> I am not experienced and an expert on this PVC overflow but I learned a lot during my research and observing my system running steady for at least a couple of weeks now with the livestock. Prior to that I run tests for a week.
> For the U-bend going over the top of your tank (bracing and width of acrylic at 6"), I don't think there is any problem with that distance. On mine using 1.25 in. PVC, it is already 3 inches. In your case you will need to use larger size PVC to handle your much higher flow rate requirement. At 2 in. PVC., you will probably find that distance to be close to 5". How this PVC overflow system works is not dependent on this distance. You might observe slightly lower flow rate capability if this distance were upward of 1 ft. or something like that but I don't believe this distance is of concern.
> Most likely you will need to run 2 overflows. I don't suggest you use PVC larger than 2 in. because the price difference is quite big after that.
> Maybe you can build one overflow using 2" PVC and the second overflow using 1.5" PVC. The 2" overflow will be your main overflow and the water intake level will be placed about 1/2 inch lower than the second smaller overflow. Why lower? because your primary overflow will take in most of the water and will be full and be mostly silent. The secondary smaller overflow will take the rest of the flow but will not have to work so hard and stay quieter without having to result to being full.
> Hope this makes sense.


Cheers, Thanks for the reply. I am really leaning toward trying this system before i bring out the drill. No point in putting holes in the tank if you don't have too! Especially when its so cheap to build one of these.

I was thinking of using ABS instead because of the color? Or is that a bad idea?


----------



## Captured Moments

AWW said:


> Cheers, Thanks for the reply. I am really leaning toward trying this system before i bring out the drill. No point in putting holes in the tank if you don't have too! Especially when its so cheap to build one of these.
> 
> I was thinking of using ABS instead because of the color? Or is that a bad idea?


I don't know enough about ABS so I am not able to answer you. I sort of quickly researched it a short while back and found that some people have used it in some various types of applications and it was reported to be OK. My Co2 reactor in one of my tank is built using ABS. It's basically a 2 ft. long ABS pipe with the ABS fittings on the ends.. It's hooked up to the outlet of my XP3 so lots of flow go through it.. seems ok and it has been like that for close to 2 years now or more..
But then would you be able to find all the fittings you need for ABS and is it ok to glue PVC to ABS if you were to mix them?

With most overflows, there is the remote possibility that at some point the siphon can be broken. There is the saying that what can go wrong will go wrong... Well that's why I ordered the pump stopper kit to avoid a flood and stop the pump if the overflow were to loose its prime. By the way, you need to come pick up yours.


----------



## jkcichlid

If you wanted darker color pipe rather than painting it, you could go with Schedule 80, it is dark gray pvc. More expensive but would only have to be the section and fittings in the tank
If you wanted to do black ABS, there is a PVC/ABS transition glue or you could adapt with a threaded fitting at a convenient spot


----------



## Captured Moments

Next is the return build from the sump to the display tank.

The pump is a Quiet One 4000. The outlet from the pump is 1" MIPT (threaded) to which I screwed a union fitting directly to it for ease of dissasembly. Again I used 1 1/4 in. size PVC parts for the return although it is not necessary and an overkill. I wanted however to maintain consistency in sizes in all the components and have the option to be able to re-use some parts. After the 1" union I had to use a reducing adapter 1" MIPT on one end and 1 1/4" glue on the other to connect with the rest of the plumbing.










The T-fitting splits the return feeding into 2 ball valves. The ball valve on the left is effectively a bypass and it allows more or less of a regulated flow from the pump to be returned to the sump.
By setting it up this way, it allows you to fine tune the flow going back to the tank in case you want to match the rate of the overflow to a particular level. Also not sure if it is really an issue but by limiting the return flow in this manner allows the pump to operate unrestricted with minimal back pressure. In my particular instance you will notice my bypass ball valve on the left is mostly closed but I somehow want some flow to return to the sump for added circulation. Almost all the pump output is returned to the tank.

































Again quite a few threaded connections instead of gluing in this section (threaded elbow, nipples, adapters, valves, union). After the return ball valve (horizontal one), I simply screwed a hose barb fitting to the end of it.








I used the Laguna Flex PVC hose 1 1/4" size and connected to the fitting. After that it is just a short trip to the return which will be covered next.

Tip: Connecting the hose barb fitting to these Flex hose.
Some people will probably agree with me that it is very difficult to mount these types of hoses onto the barb fitting due to the tight fit between the two. Even dipping the tip of the hose into boiling water to soften it up did not work either. The end of the hose became too soft to be able to push it against the fitting. It was simply collapsing on itself.
What works very well is this. Heat the end of the hose in boiling water to soften the general area until it becomes pliable enough. Use a rag or a towel to avoid burn as the hose will be hot. Quickly pull the hose away from the boiling water and with the rag grab the hose in one hand while putting the barb fitting to the end of the hose with your other hand. You won't be able to push it in much. Cover the enitre area with your rag making sure your hand covers the hose and part of the fitting. Whack the end against a flat surface like a chopping board a few times. You will probably need to repeat this process about 2 more times.


----------



## 2wheelsx2

Be careful of that flex hose. I used to use that to drain my 125 via the FX5 and wherever there was stress, the hose would start to get hairline cracks. This always happened to be where I have clamps on the hose.


----------



## Captured Moments

2wheelsx2 said:


> Be careful of that flex hose. I used to use that to drain my 125 via the FX5 and wherever there was stress, the hose would start to get hairline cracks. This always happened to be where I have clamps on the hose.


Before I put the clamp on one end of the hose, it was leaking which I found kind of odd. My belief is that the clamp is to secure the connection and not to do the sealing. The tight fitting ribs on the barb and the hose should be doing the sealing and not the clamp. Maybe I should replace it with something else. Do you have any suggestions?


----------



## 2wheelsx2

Braided hose might be your best bet, depending on the curvature that you would need.


----------



## Captured Moments

Next is the final return to the display tank. In my case I made a simple "U" shape to hang over the back of the tank. I used 45 deg. elbows for the loop rather than 90 deg. to reduce friction loss and head pressure.

















All the parts are glued together except for the barb fitting on the intake side with the hose clamp. I extended the return quite deep into the tank because I wanted the return water to be released towards the bottom of the tank. I just fitted a 45 deg. elbow to the end of the return. If there is a power outage and the return pump stops, the return would act as a siphon and the water will drain back into the sump potentially overflowing the sump. This can happen in my case since the return outlet is quite deep into the display tank and most of the water in the display would be siphoned out back into the sump. To prevent this from happening I have drilled 2 small holes in the return pipe about 1 inch below the water line. 2 holes instead of one in case one of those hole is plugged for extra safety. These holes act as siphon break and will pull in air to break siphon once these holes are uncovered. You can see the holes in the pictures. The last picture shows where the water stops when I shut off my pump.


----------



## mikebike

Thanks you very much for providing all the details and photos.


----------



## Captured Moments

I am happy if somebody can use this information to help them build something similar. It's not the prettiest thing I have to admit given the white colour of the PVC pipe but you can paint it black or you can build some kind of fake corner wall out of black acrylic to hide the pipes. This is a bit of the "*******" approach I suppose but it is a build on a budget and I find it works very well. No need to add baffles or anything to the sump. I just use a 90 gal tank as my sump that I wasn't using. There is no partitions, no baffles in the sump so I can always re-use the tank for normal usage if I want to in the future. All the filtration is done in the storage cart which will be my next coverage topic.


----------



## Captured Moments

Next to be covered is the filtration system.
I bought a 4 drawer storage cart at Superstore.. the ones you use for home to put kid misc. small toys or what have you. Don't install the wheels at the bottom. My 90 gal tank is 24" high and the cart is around the same height maybe exceeding it by about another 1/2" or so. It cost me around $30.. can't remember the exact price. Also, the unit is modular and each level can be taken apart so you can rearrange the drawers if you want. Mine came pre-installed with the 2 small drawers at the top and the 2 large drawers at the bottom. Since I was converting the unit into a Wet/Dry filter, I rearranged my drawer order to be 1 small drawer at the top followed by the 2 large drawers in the middle and the last small drawer at the bottom.










Cut a hole on the top cover to accomodate your drain pipe. I ended up cutting it in half lenghtwise and broke off the locking tabs so that you can easily remove the cover for quick inspection of the drip tray and removal of the filter floss media for cleaning. My 90 gal. has a center brace and it was not possible for me to pull out the top drawer without hitting the center brace.. so I had to devise a way to access it from the top.










The top drawer acts as a drip plate and mechanical filter with filter floss to capture the bulk of the debris. Because it is a drip plate, I needed to find out how many holes to drill at the bottom of the drawer. The idea is to have a nice even drip across the entire bottom of the tray. If you have too many holes, the spread will not be even as some of the water will not even reach some of the further holes. If you have too little holes, you risk overflowing the tray as the holes will not be able to keep up with the input flow especially after you put in the filter floss and they start clogging up. For a wet/dry filter, you want to achieve a nice even shower to the bio media below. What about hole size? what size hole to drill? During my research, I couldn't find a definite and ideal hole diameter size for the trickle effect. I decided to use 5/32" diameter size for my holes. If the holes are too small, they risk clogging up too easily. If the holes are too big, you will end up with lesser holes and your spread will be further distanced apart thus losing out on the benefit of the wet/dry. After I settled on the size that I wanted (5/32" drill bit), i had to do a bit of math.
In theory you want to match the surface area of your drain pipe to the surface area of all your holes combined on one tray. I am using 1.25" size PVC for the drain but that is the nominal size and the actual inside diameter of the pipe is actually closer to 1.5" in reality. Diameter is 1.5 inch, Radius is 0.75 inch.

The formula to calculate the surface area of a circle is: A = Pie x r square. Pie is 3.1416, r is the radius.

So the surface area of my PVC pipe drain is: A = 3.1416 x (0.75)²
A = 3.1416 x 0.5625
A = 1.76 in. square (in²)

Now that I know the surface area of my PVC drain, I need to know the surface area of one hole at 5/32 drill bit size.
5/32" = 0.15625"
radius = (0.15625 / 2) = 0.078125"
A = 3.1416 x (0.078125)²
A = 0.019174804 in. square (in²)

Therefore the number of 5/32 holes needed to match the surface area of my drain is:
No. of holes needed = (1.76 / 0.019174804) = 92 holes.

I decided to go with 99 holes instead to account for "real life scenario" and given the fact that the filter floss sitting on top of the holes will somehow restrict the flow a little bit.

















Because of the way this storage cart is built, notice how the white frame support extends underneath the tray so it is not a good idea to drill holes too close to the outside edges especially in the front of the tray. In the pictures below, notice how I traced the outline with a sharpie pen to constrict my holes to a specific area only. In this manner all the drip flow will drain down directly to the tray below and not hit any of the frame below it. In my case my effective surface area is 11" x 9" so I made 9 rows of 11 holes each drilled 1" apart. Note: After some testing, I had to fine tune a bit and drilled a few more holes (about 8 more). Ideally I want my water level in the drip tray to be at around 1" high.

























Drilling the holes was easier than I expected because I was worried that the plastic would crack while drilling the holes. The holes were clean and I used a regular 5/32" drill bit, nothing fancy. Just lay a small sheet of plywood or something similar underneath the tray while drilling.
In actual use, the water level in the drip tray tends to creep up as the filter floss gets dirty and things clog up a bit. That is why I drilled a series of 1/4" holes at the top and front of the drip tray so that if the water level were to rise to that level over the course of a few weeks, it will overflow through these escape holes rather than have the tray overflow. These escape holes simply drip into the sump. If you hear this water dripping noise, it means it is time to clean your filter floss.










As a result here is the shower effect from the drip tray:

























Repeat the same thing and drill the holes on the other 3 trays except that I drilled a few more extra holes on those trays because they are not acting as drip plates so you want the flow to be able to flow in and out rather easily.
As mentioned, the middle 2 trays are the 2 large trays and contain pot scrubbers. You can use bio balls. The last small tray at the bottom contains bio media. In my case I have used whatever I have available at the time such as lava rock, crushed coral, oyster shell, ceramic rings. You can use other media like Purigen, coco puffs, etc..

BOTTOM TRAY:


----------



## Captured Moments

PICTURES OF MY FILTER SETUP CONTINUED.


----------



## 2wheelsx2

Nice setup. I'm considering that tray design too. Why did you not consider a foam prefilter like Poret instead of the floss? It would be reusable and would probably clog less easily too. I guess the floss is really cheap and the cost is negligible, but was just wondering about the clogging.


----------



## Captured Moments

2wheelsx2 said:


> Nice setup. I'm considering that tray design too. Why did you not consider a foam prefilter like Poret instead of the floss? It would be reusable and would probably clog less easily too. I guess the floss is really cheap and the cost is negligible, but was just wondering about the clogging.


Yes I thought about using a large pre-cut piece of foam like you suggested and I am pretty sure it will work better than filter floss and also probably less likely to clog up. True to filter floss being the cheapest and it is the only thing I have available.. maybe spend a few more bucks later and try the foam but right now I am so preoccupied with this new car buying frustrating business with my deposit, the scratch and the kilometers issue..
With the filter floss, right now I have to clean it every 2 weeks or so. I also thought about using a filter sock but I never used one so I don't know how well they work.


----------



## Captured Moments

I haven't updated this thread for a while. The overflow system is working fine and never lost prime. The only maintenance issue is to top up the water as the water level in the sump slowly decreases due to evaporation. I also need to clean the filter floss media on the top tray every week and a half roughly.... and water change of course.

Even though the overflow system never lost prime I couldn't help worry about the what if scenario. With no prevention system in place in the event of the drain clogging up or loosing prime, the pump will simply continue pumping and the main display tank will overflow.

During my research I came across a pump stopper kit from Aquahub. Basically it is a float switch connected to a relay valve that turns off the pump should the float switch be activated by a rising water level. They can also be configured to be the opposite. I'm just a noob at this stuff and I think Gordon (Gklaw) makes extensive use of them in his Discus grow out sump setup and his automated diy water change system.
I started a group buy a while back for the pump stopper kit from Aquahub so that there would be no shipping charge. 
Shortly after it arrived I started to assemble and install the kit. The instruction sheet printout that came with the kit had an instruction line cut off on the bottom but you can download a better copy of the instructions from their website. 
Of course we need pictures:








...
















...









Drill some holes on the bottom of the snail/slosh guard and on the screw on cover for air to escape.








...









To me the hardest part of this whole assembly was to measure the distance I wanted the float switch to be relative to the top of the tank and shape this "mold a bracket" accordingly so that
the float switch is at the right level and trigger the relay at the exact maximum water level I want.








...
















...
















...


----------



## Captured Moments

Continued. I have more pictures.

The float switch is done ready to be hung on the side of the tank.








...









Need to buy a 2 prong short extension and cut it in half close to the female end.








...









Install the Reset switch and the led indicator light. By the way that project box does not come with the holes pre-drilled. I had to drill the holes before I could install the indicator light and the reset switch. Also, you 
need to drill a 3/4" hole on the other end for the electrical cords. You need a hole saw for that. I thought I had bought a hole saw kit before and I searched everywhere but couldn't find it.. so I went to Home Depot and bought myself just the 3/4" size one.. then shortly finding my old set after I had used it for the hole when putting it away...waste of money.








...
















...
















...
















...


----------



## gklaw

Captured Moments said:


> I'm just a noob at this stuff and I think Gordon (Gklaw) makes extensive use of them in his Discus grow out sump setup and his automated diy water change system.


Thanks Christian  The stuff I do in my discus grow out is just basic power on and power off. I managed to overflow the display - left the fill sump switch on while water is being pump from the sump. You Pump Stopper Kit would have avoided that - it is still in the box. I think I will have that planned for future setups.

BTW, you are the DIY king  Nice step by step and photo.


----------



## gklaw

Captured Moments said:


> I'm just a noob at this stuff and I think Gordon (Gklaw) makes extensive use of them in his Discus grow out sump setup and his automated diy water change system.


Thanks Christian  The stuff I do in my discus grow out is just basic power on and power off. I managed to overflow the display - left the fill sump switch on while water is being pump from the sump. You Pump Stopper Kit would have avoided that - it is still in the box. I think I will have that planned for future setups.

BTW, you are the DIY king  Nice step by step and photo.

Electronic is one of the hobby on the list to be picked-up  I did a tiny bit of soldering couple months back, I was dumb enough to grab the iron by the tip - ouch!!! This tiny little stick is more dangerous than my 5HP table saw hehe.


----------



## Captured Moments

More electrical connections.










Everything tucked in inside the project box








...









Testing with an air pump and manually trigger the float switch to activate the relay and shut off the pump.










Lights out.. You can see the led light indicating that the pump is shut off. You need to press the Reset switch to reset everything back to normal otherwise the pump will not turn itself back on.








...









Here you go... the finished system. Just have to put the control box underneath the stand.


----------



## Captured Moments

Time for an update on my overflow sump system. The entire system has been running excellent since basically the beginning of the year and it never lost prime once.
The only times it stops is when I change the water (every 2 weeks or so). I just drain off the main display tank and when the sump is nearly empty, I then shut off the pump to drain the main tank.
Once everything is done I simply plug the pump back on and the overflow simply resumes itself.

Recently I just made a small change to my filtration system having to do with the filter floss I was using on the top drip tray. It was clogging up way to fast and it wasn't very effective.

Before change (left pic) and after (right pic)








..









I am using the grey filter media pad I bought at J&L Aquatics for $25. It comes in sheet size 19x24 inch and is 1.5 inch thick. Reusable and it should last me a very long time.
They come in 4 colours (black, blue, green, grey) for different size of particles. This material is quite stiff and it would make an awesome tank divider as well.








..









cut a piece to size to fit the tray








..


















Et Voila! works great so far.


----------



## jbyoung00008

That really came together nicely. Great pictures to show how it was made.


----------



## Captured Moments

That was a long time since I have updated my journal. Anyhow I just wanted to let people know that the PVC overflow system that I built has been extremely reliable. Since it started operating in 2012 it has never lost prime once. The whole system is practically maintenance free and I haven't touched the overflow once since. I would clean the drip filter in the sump every few long months in between..shutting off the pump at that time and restarting it once the filter mesh cleaned. Everything just resume operation, no lost in prime.


----------

