I would avoid any kind of chemicals that are used in the aquarist hobby.

If you want to increase or lower the pH of your water, you can add crushed coral or driftwood and almond leafs.

Anything for parasite or bacterial control, it would be best to have a separate quarantine tank.

Adding something like prazipro or melafix could have some dire consequences. The water will evaporate into the enclosure, and cover everything inside.

Chris