I have 4 sizes
small....these sell at non aquarium stores (e.g., 40) you can do a lot with these, but also with lots of limits
medium...you can create a full blown eco system (plants, shoals, mixed varieties), although you may have limits on which species (55 to 225)
big...you can raise a full gown tank buster (~225 to 700), with larger fish needing the larger size (not every tank buster of course, but 80-90% I think fit this)
huge...I've read so many times that you can't keep "2" of this species or that species in the same tank, that my definition is based on that. If I can keep 2 of "those" safely than it's huge.
small....these sell at non aquarium stores (e.g., 40) you can do a lot with these, but also with lots of limits
medium...you can create a full blown eco system (plants, shoals, mixed varieties), although you may have limits on which species (55 to 225)
big...you can raise a full gown tank buster (~225 to 700), with larger fish needing the larger size (not every tank buster of course, but 80-90% I think fit this)
huge...I've read so many times that you can't keep "2" of this species or that species in the same tank, that my definition is based on that. If I can keep 2 of "those" safely than it's huge.

