I agree with Silver. ACFs are carriers of chytrid even if they do not get it but the other frogs you add to the tank will be be susceptible. They really ought to be in a species only tank. If you are adamant about keeping the bullfrogs with them, they could most likely get chytrid and I am not sure if they can be treated the same as we treat adfs. Do you have any of the BC bath materials on hand. I also don't know if you can treat the acfs for chytrid to ensure other amphibians won't get it using the BC baths. I think Silver, MAC, or JBOT would know more than I do. BUt the problem also lies in the fact that the chtyrid spores are in the tanks and can only be removed in you clean everyting the tank, nuke it, let it dry thoroughly, and treat all inhabitants. I have even thrown away all decor and gravel to be on the safe side. Even my lfs, will not put anything else wit the acfs at their store except plants, and I have a probelm with that as well b/c the spores could contaimnate the plants as well so I don't like that they sell the plants to customers if they are for chytrid susceptible crotters. With chytrid running amuck right now, in all honesty, I think its only responsible thing to do is keep an acf only tank, even if your plans are temporary. Sorry to be the bearer of bad news, but I can'r express enough how horrible chytrid is and we (aquarists and citizens) must realize the detrimental effects it is having on amphibians worldwide and should all do our part to try and curb it. HTH, Stephanie