Quote Originally Posted by MsLockwood View Post
...I'm worried the water conditions in his tank aren't quite right and would like some help finding the appropriate water conditioner...
From your description appears maybe your frog was going into estivation. Have no experience with that so will let others answer your question. Also can find lots of good info at the Pacman care article: Frog Forum - Pacman and Horned Frogs - Ceratophrys - Care and Breeding .

IRT conditioners; any made for reptiles or fish should be fine. Try and find one that not only takes care of Cl, but also detoxifies chloramines and heavy metals. I like Seachem products and use a conditioner named "Alpha" from their saltwater aquarium Vitro line.