# Lace rock & gh/kh follow-up



## Morainy (Apr 21, 2010)

A few months ago, I asked whether lace rock affects gh and kh. 

The lace rock has been in my tank for about 4 months now, and I can tell you that it does not affect gh or kh. It looks almost like it would dissolve in water and it does give off bits of rock and sand at times. 

However, I have to add a pinch of Equilibrium to each bucket of water I put into the tank, just to keep the water at "very soft." 2 drops gh, 2 drops kh. 

So, in case you are wondering about this new rock (grey and quite pretty -- you can see a pic in Atom's Eheim Aquastyle journal), you don't have to worry about it making your water harder.


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## 2wheelsx2 (Apr 21, 2010)

Good to hear, I haven't seen this stuff in person, but based on the properties and the photos I've seen, I'm pretty sure it's ocean quenched basalt which would be mostly silica.


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## CRS Fan (Apr 21, 2010)

Morainy said:


> A few months ago, I asked whether lace rock affects gh and kh.
> 
> The lace rock has been in my tank for about 4 months now, and I can tell you that it does not affect gh or kh. It looks almost like it would dissolve in water and it does give off bits of rock and sand at times.
> 
> ...


I think it can and does affect your GH/PH depending on it's source. It is a common name used in the trade. Here are some excerpts from an aquahobby.com thread:

"I was under the assumption that lace rock, such as Utah lace rock, was fairly inert. I have seen it used in many fresh water tanks, from rift lake cichlid tanks to tanks with rainbows in it. I may be way off on this though. Try putting some vinegar on a piece. If it fizzes then it will raise pH and dh"

"This is an example of "common" names causing confusion. *In my area "lace rock" is a completely inert product that will not effect pH.* I have used in most of my tanks for years."

"*That looks like Utah lace rock also known as base rock. It is an old stone geologicaly speaking and is innert as Tommy pointed out.* I am not a rock hound so I can't tell you the specifics on what it is or what made it...any of you people know?"

"I don't think it is possible to let the lace rock leech. *The lace rock around here is limestone* - which is what I think you are talking about. If I am correct, its own chemical makeup slowly dissolves. This increases your pH and KH. Many times folks I know use this or coral to buffer their water - especially when using a carbo plus system."

Best regards,

Stuart


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## 2wheelsx2 (Apr 21, 2010)

CRS Fan said:


> I think it can and does affect your GH/PH depending on it's source. It is a common name used in the trade. Here are some excerpts from an aquahobby.com thread:


Entirely right. I've examined a lot of "slate" which wasn't even metamorphic rock. And things like Mexican Bowl Rock, Flagstone, Lace Rock, all mean different things to different people. But limestone is limestone, so in that quote, the seller misled the buyer. Limestone is pretty obvious.


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## gklaw (May 31, 2010)

Can't argue with a geologist  I never trust any trade names. I little knowledge of rock goes a long way.

I always thought Lace rock to be the "feather rock" super light weight stuff I find at landscape supply which sounds like Gary's descrip.

Google shows various and resembles what IPU used to sell as Tufa rock. I have used a huge chunk as the base of my reef. From what I can see, that thing does not appear to be pure silica. I would suspect that to have some CA carbonate which will leak into the water - perfect for my SW. 

Again, not challenging Gary's expertise. Just pointing out that blindly following trade name is dangerous. Some store may not know what they are actually selling.


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## 2wheelsx2 (Apr 21, 2010)

Yes, trade names are unreliable at best and totally misleading and wrong at worst. But unless it's easily dissolved rock like Tufa (my 20 gallon CO2 injected tank went through Tufa rock at very high rates - a fist sized chunk in 6 months), which is almost pure calcium carbonates, there really isn't any danger in our water, which won't dissolve much of anything, unless no water changes are performed.


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## Morainy (Apr 21, 2010)

You're all quite right. The name isn't specific. The "lace rock" that I'm referring to came from Aquariums West. It doesn't look as inert as granite, that's why I was wondering... but it doesn't seem to be limestone.

I'll attach a photo.


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## 2wheelsx2 (Apr 21, 2010)

It isn't apparent which it is from your photo, so I googled around and found examples of what Stuart and Gordon are talking about:

Lace Rock that's basalt: Smith Rock Decorative Stone Decorative and River Rock
Lace Rock that's calcium carbonate (at Aquariumsupplies.ca of all places) - 40 lbs Lace Rock South Seas


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## Morainy (Apr 21, 2010)

Very interesting! 
From the pics, it looks like the grey lava rock from Utah. Cool!



2wheelsx2 said:


> It isn't apparent which it is from your photo, so I googled around and found examples of what Stuart and Gordon are talking about:
> 
> Lace Rock that's basalt: Smith Rock Decorative Stone Decorative and River Rock
> Lace Rock that's calcium carbonate (at Aquariumsupplies.ca of all places) - 40 lbs Lace Rock South Seas


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