Seattle_Aquarist

Hi ShayF,

Sure, here is the link to the thread. The post is a little over 1/3 the way down the page, dated Wed Apr 12, 2006 9:09 PM. Don't even ask how long it took me to find this reference. I did a lot of digging for almost a month and found posts on countless different forums. I found guesses of anywhere between 1% to 3% concentration of Glutaraldehyde in Excel. This is the only thread I was able to find where testing provided the results.

ShayF

Seattle_Aquarist, thank you very much!

MotionInsilver

was piqued on trying this out to eliminate alage issues as I'm already having issues with a nano setup within 2 weeks as well but its kinda confusing on which solutions to get on that site? as there are different solution percentage and even "biological grade"

Seattle_Aquarist

Hi MotionInsilver,

Unless you have a lot of aquariums, or large aquariums, it is probably cheaper to use Seachem Excel. It is also easier to get in most areas. Here is a link that helped me solve a lot of my algae issues. Along with dosing Excel I did 2X week 33% water changes and kept the lighting period short (6 hours or less), especially when the tank is new, helped a lot! BTW, I use 50% Biological Grade.

dunderman

Be very careful with glutaraldehyde. Not only is it very toxic, it is also carcinogenic. Additionally, it has a very short shelf life (30 days) once it has been activated. A gallon for less than $20 may seem great when compared to $12 for 16 ounces of Excel, but unless you have dozens of tanks, you will run out of shelf life long before you run out of glutaraldehyde.

jcali10

Why would you activate it? Do you have medical or dental appliances to sterilize? I've always just thrown away the little bottle of activator that came with the gallons of Metricide I've purchased. The activation date and expiration date apply to it's use as a sterilant. Anyone using glutaradehyde as a source of carbon would not activate the product.

Zapins

Hmm... what exactly does the activator do and do plants use the active form or the inactive form?

jcali10

zapins wrote:

Metricide which is a sterilant and high-level disinfectant is 2.6% glutaraldehyde and 97.4% inert ingredients (water). A gallon comes with a 3.8 oz bottle of activator for it's intended use, sterilizing medical and dental equipment. Once activated, it will last for 14 days and should maintain a glutaraldehyde level of at least 1.5%. The activator will turn the glutaraldehyde green, I'm just reading off the label.

The label also says it is a violation of Federal Law to use this product in a manner inconsistent with its labeling.

Seattle_Aquarist

Hi jcali10,

I purchase 50% concentration Biological Grade Glutaraldehyde; it does not have an "activator". In fact, if you have read this thread in its entirety, you would know that the "activator" that is provided with some of the products that contain Glutaraldehyde is not used.

Glutaraldehyde has several applications, not just as a "sterilizing agent". Here is a link to Wikipedia that indicates some of its' various uses including that of an algaecide. A polymerized version of Glut is the active ingredient in Excel so it is being used in a manner that is being used in a "consistent manner". I hope this clarifies it for you.

Zapins

Thanks for the responses so far, but they don't exactly answer what I was curious about. I'm interested in understanding the activator more, what does it do to the inactive glut to change it into something that will expire?

Why is it 14 days and not 50? I assume whatever change the activator does is unstable which is why there is a 14 day life time. I also assume the activator chemically changes the glut. into a more destructive form, but what is that form and is that the form that plants use or is the inactive form the one plant use or alternatively can plants use both the inactive form and the activated form?