It really is a matter of preference and also whether you plan on breeding them. Teresa is absolutely right. Reidi can come with very colorful variations and aren't difficult to maintain, but are difficult to raise the fry. Southern erectus can also be colorful but not quite as brilliant as reidi, but the fry are easier to attempt to raise. Northern erectus which I have, are as colorful as southern, but not as colorful as reidi, and their fry are as difficult as reidi. So, if you want to breed, I'd start with southern erectus.