It all depends on the tank that you are going to keep them in. They do really well in small very heavily planted tanks with lots and lots of moss.
I had 5 in my 35l tank and they were fine for around 4 months then all of a sudden BOOOOM they had a population explosion.
I think the best thing you do for them is give them the best water. So a fully cycled established tank if you want them to trive as apposed to just survive.