It is downright cruel to keep an African Clawed Frog in 6.6 gallons and completely ridiculous to keep them in a 5 gallon tank. If you keep an ACF in such small aquariums, you're doing it wrong and your frog will not live a normal healthy life. These frogs can live up to 15 years or more and I highly doubt you'll see a lifespan even close to that in such an inadequate tank.
These frogs should be kept in a bare minimum of 10 gallons and I think that is even somewhat cruel. The best tank for a single frog is a 20 gallon long. Adding snails will make the situation even worse.
An ACF -can- tolerate poor water conditions (which does not mean they SHOULD be kept in bad conditions, eventually they will succumb to poor conditions and will suffer..) but a snail cannot. A dead snail rots quickly and fouls the water and will kill the frog.
The only acceptable snail to keep with an ACF is an Apple/Mystery snail and these snails ALSO create a lot of waste and WILL die in poor water conditions. Both ACF and snails are -huge- waste creators, ACF poop like goldfish on steroids, would you put a goldfish in a 6.6 gallon aquarium???
Your frog will also want to swim, he can't swim much in a tank of that size, even if it is a 3 inch male there is not enough space for the frog. You'll also need to lower the water level in a 6.6 so the frog can breath and for plants you'll need add substrate.. your 6.6 gallon is now ~3 gallons.
I keep 3 ACF in a 40 gallon breeder and I assure you they need that space and they are very active swimmers. I couldn't imagine keeping them in anything less..
Think about it this way.. would you keep a German Sheppard in a 2'x2' room full of smoke and it's own feces 24/7? Do you think it would have a long healthy life?
Animals like ACF can't convey the stress you put on them, they have no way of telling you that their health is slowly fading, they may cope for a while but eventually dropsy, red leg, fungus, ammonia burns, ect will occur and the frog will die.. and that will happen I assure you.
Last but not least these frogs are sensitive to fertilizers, so adding them to an aquarium with an ACF which is already in woefully poor conditions will simply exasperate an already really really bad situation.
So if you want an ACF then do it right or don't bother, same goes with any other animal you wish to keep, period.
*ADF (African Dwarf Frogs) would be perfectly fine in a 6.6 gallon, if you want aquatic frogs that's your best option.
Last edited by Michael M; 11-17-2012 at 02:07 PM.