I've got a single male krib in each of my 29 gallons tanks. They seem to chase everything. I have read that they are great community fish on several sites but I haven't seen many fish they haven't jumped at or chased. I've even seen one swim to the upper layer to bite an angelfish. I have noticed that my angelicus loaches are ignored and can swim all around the krib without causing him to attack. I've even seen them take food from him and he doesn't do anything. These guys have only been in the tanks for a little over 24 hours so maybe they will settle down some in time.