I have a small (6Gal) planted aqaurium - it has several low light plants, using eco complete substrate, temp is 78F, it is a new tank, completed cycling a couple weeks ago. I've been testing twice a day and ammonia/nitrites are a steady zero, nitrates range between 20- 40, doing 30% wc weekly. The tank has 5 ember tetras, 3 endler's live bearers, and one betta. I needed a tank for the betta (the filter in his tank broke so I am recycling with a new filter - should only take a couple weeks with a hot start). The tank is a fluval edge but while the betta is in it I am keeping an air layer at the top... anyway, I have a single kuhli loach in the tank to eat the food that hits the bottom. Since the fluval edge isn't supposed to have an air layer at the top I couldn't use my preferred pygmy corys for this task, and the kuhli was the next smallest bottom feeder I could find. I have never kept this fish before and don't know its eating habits. He doesn't appear to be eating. There is flake food on the bottom but he seems to ignore it. I have tried feeding him shrimp pellets but he ignores those too. Also, he seems very agitated, or active, not sure what is normal for him - he's been in the tank for a week so I don't think it is transport stress. From what I've read on him it sounds like he should be in a group, which a six gal tank can't accommodate. I have a heavily planted 20L and 55hex that I could move him to if he needs to have more kuhlis to keep him happy, but if I do that I will have to find a bottom feeder for my 6 gallon. Also - I have 4 full size panda corrys in the hex - not sure the tank can accommodate 2 schools of bottom feeders....? Need some advice - is the kuhli behaving normally, do I have to give him some kuhli buddies to swim with and move him out? If so, the choices are a 20L with 5 pygmy corrys or a 55 hex with 4 panda corrys, will 3 kuhlis fit in with those other bottom feeders? Or do I need to take him back to the store?