All are right. This is the closest to the price I usually buy it for... Amazon.com: MetriCide® 28 High-Level Disinfectant / Sterilant (1 gallon bottle): Health & Personal Care.
Make sure you wear gloves when dealing with concentrated glutaraldehyde.
I wouldn't worry about Excel in the tank, and just be careful with the diluted solutions (like Excel), gloves not necessary but do take care not to dump in on yourself or anything.
All are right. This is the closest to the price I usually buy it for... Amazon.com: MetriCide® 28 High-Level Disinfectant / Sterilant (1 gallon bottle): Health & Personal Care.