I pygmy should do good, but I believe they only have like a 6 month life span, and you dont normally know how old they are when you get them...
I also have a 30g with a Bimac, most people here say a 30g is to small for a Bimac, but I have noticed a good number of people with 30g.
So I may be transfering tanks in the future, but for now there are no problems.