# Metricide Expiration



## jobber (May 14, 2010)

Thanking a BCA member who offered me a half jug of metricide o use. However, the bottle of metricide is due to expire in March 2011. I know this question may have been asked before, but my researching skills isn't as good right now, so a quick answer from a member on BCA would be greatly appreciated. 

My question is:
1.) can expired metricide be still used for the tank?
2.) have you used expired metricide?


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## CRS Fan (Apr 21, 2010)

No idea, Ming. I guess I should check my bottle for the expiration date too.

Best Regards,

Stuart


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## jkam (Apr 21, 2010)

I forgot to pour a little to keep for myself.. LOL 

I might have to come by and grab a little from you hahahahah


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## kelownaguy (Jan 1, 2011)

IMO,the expiration date only applies to unopened bottles.
Opened ones expire sooner.

The name says it all- "Metricide 14" =14 day life.

The instructions say even more:

"Do not use beyond 14 days or sooner as indicated by a 1.5% glutaraldehyde
test indicator."

Draw your own conclusions.


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## Captured Moments (Apr 22, 2010)

kelownaguy said:


> IMO,the expiration date only applies to unopened bottles.
> Opened ones expire sooner.
> 
> The name says it all- "Metricide 14" =14 day life.
> ...


The "14 day" refers to the length of time that the metricide solution is good for once it has been activated with the activator that comes with the solution. Once the Metricide solution is activated, it is supposed to turn green and it's will be good as a disinfectant/sterilisant for 14 days. That is if the Metricide is used for its intended purpose.

In aquaria, a lot of people have been using it as a source of carbon in their planted tank. Obviously the activator is not used in this case so the 14 day time limit doesn't apply here.

I am not sure on your comment about "the expiry date only applies to unopened bottles. Opened ones expire sooner". I have no reason to believe otherwise. Maybe someone else can confirm that.

Anyhow, we are not using the Metricide in as strict and regulated environment as in what it is intended for. Perhaps we can relax on the so called expiry date especially if we are only using it as a source of carbon. I have a full bottle that is expired now since beg. of January thanks to a member who gave it to me. Thanks. Unfortunately I don't use it because I run pressurized Co2 but I for myself wouldn't hesitate in using it and observe. Suppose I could run the experiment, turn off Co2, use Metricide...
Is there expiry date on Flourish Excel?


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## kelownaguy (Jan 1, 2011)

You may well be correct.

I`ve seen different suggested shelf lives for properly stored unopened bottles ranging from 1-3 years.

I emailed Metrex for clarification.

It would be nice if someone tested an old opened bottle w/the test strips.
Some medical type person w/access to test strips perhaps?

In the meantime,you can scare yourself w/toxicity info here:
Glutaraldehyde


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