How big of a tank does 1 need?
Ehh they don't really swim, so that's not going to be a factor on tank size. They will come out occasionally and make a lap or two, then go back into their cave.
I would say around a 20-30 gallon AIO with added filtration would be the bare minimum for them. A 30 gallon with sump (like my Deep Blue) is prefered. As long as they can stretch out completely and have a few different hidey holes they are comfortable.
Its filtration for a predator that is the problem. Instead of small frequent meals, like feeding normal fish once or twice a day, they eat large infrequent meals that puts a big load on the bio filter, then none at all for a few days up to a week or even more in a hunger strike. Really small tanks can't handle the bio load.
It's like tossing a dead nano fish in your tank every two to three days. A large tank will never notice, but a small tank will have a build up of nutrients and maybe ammonia because the bio filter will get overwhelmed. I'm pushing it with my tank choice, but I have a trick up my sleeve I hope is going to work out...
