I can find a bunch of forum posts and articles of people using straight glutaraldehyde instead of Excel, but no one seems to follow up on the results, dosage sizes, etc. or maybe I just need to improve my search skills.

From what I can gather from the Excel MSDS, straight glutaraldehyde should work just fine, but what I can't find is the concentration of polycycloglutaracetal in Excel. Wikipedia says glutaraldehyde concentrations as high as 5.0ppm won't harm fish, but I'd still like to figure out what the recommended dosage of Excel equates to when compared to a 25% glutaraldehyde / 75% H2O or similar solution. Seachem is pretty mute on the subject so does anyone know this, or where to figure it out.

Sterilization grade glutaraldehyde is pretty easy to find:

Cold Sterilizat - DE Glutaraldehyde / Gallon - 28 Day - New York Tattoo

http://www.discountseniorsupply.com/...c=43&zmap=8142

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