None of your fish are bottom dwellers.Well i have a pair of albino kribs and they are in a 20g tank 2 mollies, 3 swords, a school of wild minnows, a golly, a flower pot, a pvc pipe, and a amazon sword plant, and like 5 grass like plants that havent grown in yet. I barely ever have deaths and i have seen my kribs attack anytihng or show the least bit aggression.