Glutaraldehyde

[LauraFrog]

Right, this is the latest aspect of water chemistry that's screwing my head up.

Glutaraldehyde (C5H8O2) is used as a fertiliser. This is directly off Wikipedia, I don't have time to look further unfortunately

A polymerized isomer of glutaraldehyde known as polycycloglutaracetal is a fertilizer for aquatic plants. It is claimed that it provides a bioavailable source of carbon for higher plants that is not available to algae. Though not marketed as such due to federal regulations, the biocidal effect of glutaraldehyde kills most algae at concentrations of 0.5 - 5.0 ppm. These levels are not harmful to most aquatic fauna and flora. Adverse reactions have been observed by some aquarists at these concentrations in some aquatic mosses, liverworts, and vascular plants. [2]


Does anybody know what the difference is between glutaraldehyde and polycycloglutaracetal? And if I manage to get my hands on glutaraldehyde through a chemical supply, can I use that?

 

[OohFeeshy]

There's a very big difference (in theory, anyway), but you're not going to find out because the chemical comapnies don't want to be talling everyone about how they make their special chemicals. The bit on Wikipedia seems a bit misleading, almost as if someone has deliberately put it there to throw people off the scent. The fact that it's a 'polymerised isomer' and the 'cyclo' prefix indicates that actually, it's not a whole lot like glutaraldehyde, the similarities being purely symbolic, as it were.

If you read the Wiki page, it also said glutaraldehyde is commonly used as an embalming fluid... bummer. Might not want to stick it in your tank, really.

 

[aaronnorth]

Glutaraldehyde is the base foundation of excel/ easycarbo, there are other chemicals added to make it safe for aquarium use so dont bother buying any - not that you can in the UK anyway i dont think

 

[Revision17]

I've been using metricide (a 2.6% glutaraldehyde) on my 30 gallon planted tank for months now (have about 1/4 of the 1 gallon bottle left). Doesn't seem to harm plants and fish, and I get very little algae. It, KNO3, and plantex csm+b get delivered to the tank twice per day via peristaltic pump.

Haven't done any super scientific tests, but I get very little algae. I'll post more detail if anyone's interested.

 

[aaronnorth]

I've been using metricide (a 2.6% glutaraldehyde) on my 30 gallon planted tank for months now (have about 1/4 of the 1 gallon bottle left). Doesn't seem to harm plants and fish, and I get very little algae. It, KNO3, and plantex csm+b get delivered to the tank twice per day via peristaltic pump.

Haven't done any super scientific tests, but I get very little algae. I'll post more detail if anyone's interested.

I am. What exactly is in it and Where do you get it from?