Bully? I’m brand new to fish ownership. I’ve cycled my tank and added 4 tetras. At the advice of the salesperson, my kids picked out 2 neon tetras and 2 cardinal tetras. 36 hours later, the fish look like they have settled in, but one of the neons (smaller than the other fish) seems to be turning into quite the bully. He is rushing at the cardinals and nipping them and then chasing after them when they swim off. Now, instead of hanging out in their pack of 4, they seem to be more spread out, with one or other of the cardinals spending time off alone. Is this just a normal relational reaction to suddenly being in a new environment with new cousins? Was it a mistake to get 2 of each? Do I send the bully to another home? Do I send the cardinals away and replace them with two more neons? The cardinals also seem to have white fluff (3 dimensional) on their sides. One patch each. Is this fungal? Or an owie from the bully? What to do???