The problem I've found with my condis is that they end up being a whole lot bigger than thought. Both of mine ended up opening up at least 3 times bigger than what they were at the LFS. I thought I was buying small ones, but in my 29, sometimes when one would extend completely, it would take up almost a quarter of the tank. Like SnF said, they like to roam a lot, so make sure you protect your powerhead intakes. Other than that, they've been real easy to care for. Just make sure to feed it enough - I've fed mine whole silversides before.