Cheetahs also don't have very much genetic diversity, and I believe cultivated coffee also suffers from the same problem.
I don't know if I buy the argument that it's not bad to inbreed. Sure you can get away with a generation or two or whatever, but when its generation after generation .... you just have to look at any of the purebred breeds of dogs or cats and the plethora of ailments that are common to those that your average mutt just doesn't have to worry about to know that this can't really be a good thing.
I don't see how the gender switching would really have an mitigating effect on any kind of problem associated with inbreeding.
You have to go through extraordinary measures, or at least measures beyond just simple tank maintenance, to raise fry, so if you just wanted a mated pair to take care of and they laid eggs or whatever ... unless you do something to catch them before they're eaten then their fate is sealed anyways. It's an unfortunate fate I suppose but it's no worse than what would happen in the wild (think about how many eggs are laid over a breeding pairs lifetime .... then think that it only takes two offpsring to survive from each pair to create a stable population .... that's a lot of mortality). And like has been pointed out, it
is a good food supply for the tank ....
