This is my first posting, I hope I am in the right forum, apologies if not, I have had my tank for nearly three months and being new I seem to have done everthing wrong, although I have kept my PH amonia and nitrite stable, I am so glad I have found the forum as I am going to buy a new big tank and be more careful this time as I have stocked the tank willy nilly, didn't mean to though and I always asked if they were community fish. I started with 6 neon tetra (20 gallon tank) then added 6 galaxy rasbora a week later, then followed by 2 zebra danios,2 harlequin rasbora,2 corys and an algae eater, I then got 2 cherry barbs,who spawned and after the that the male turned in to Satan and attacked all my other fish who all stayed in one corner of the tank (he is a long story), the zebra danios are bullies and chase everyone else but the other fish don't seem stressed out by it. Then came my biggest mistake of all, getting a male platy and two females, he literally hounded the females to death, now he is after the female cherry barb but she gives him what for when she has had enough, now on top of all that I have just lost 2 tetras after all this time and I am totally stressed about the balance of the fish in the tank, is there any thing I should do, and what fish i could move when I have set up my new tank (151 litres)