I've been cleaning out my reptile cages with aquarium cleaner so far. Its a mild cleaner and uses the same basic rules as bleach. Rinse until you can't smell it anymore.

Now I want to upgrade to Chlorhexadine. I found a 16oz bottle online for $7.99 not including shipping. It says it makes up to 16 gallons of mix. So, I have a few questions.

1) I've heard that this stuff can only keep for a certain time. How long is a gallon good for?

2) Does it follow the same rules as bleach. Rinse until the smell is gone?

3) Is it better to get the gallon jug for $28.99 (not including shipping)?

4) For two reptile tanks, how long will 16oz/1 gallon last me?