Join Date: Jul 2010
Location: Outside Philadelphia, PA
I prefer large tanks. IMO it's possible to do a lot more in a large tank, even if the fish your keeping are the same species, but with greater numbers. On the down side, if you have a large tank crash, the clean up job is massive, and a lot of work.
However, many small tanks can also work out well. For example, if you want to breed fish, you need a lot of tanks set up for spawning and grow out. Some species such as the annual killifish don't live too long, so if you always want to have them in your tank, it usually means setting up your own breeding program.
Multiple small tanks also allow you to keep species that could not otherwise be kept together.
The downside I see to many small tanks is that it takes a lot of time and effort to maintain them all at a first class level. It's usually a lot less work to keep large tanks, once you get over the initial set up.