I'm going to get some tiger barbs for my 20 gallon long, and I was wondering what a good tank mate would be. I want something that would be medium sized, like 2"-3", and something that the tiger barbs wouldn't nip at. Also, I don't know how many tiger barbs to get, I was think like 6 or 7, but would that be too much? And lastly, would corys mix well with tiger barbs? thanks for any help. 