Originally Posted by VerdantGrotto
Thanks for all the responses!
I've been thinking about it and I will be introducing them in groups of 3...
(Once i get my 55 gallon anyway)
I'm just a little skeptical of having so many bottom feeders. Maybe I will go with :
Is this too many? I also wanted to put a Clown Loach in there but that might be too much for the Lower level.
As you have space, I would increase the cory species up to five of each. Where space is limiting, 3 of a species with 2 or more species (so you have 6+ in total) is OK, but the more of a species the better. Some are very species-oriented, others less so. But there is no doubt at all that they will be healthier the more there are of each species.
And all species get along, you will never see squabbling among corydoras.
I have had up to 60 corys from several species mixed in my 90g and 115g tanks. Some certainly prefer staying within their own species more, but they all get along and chum around together no matter what. In a 4-foot 55g tank, you could have anywhere from 5-6 (if one species only) up to 30. This may limit other substrate fish though.
On the loach, as has been mentioned, this is not good. A group of 5+ is required or the fish will likely be stressed. And they get large, 8-12 inches in a 6 foot tank [minimum], but some clown loach can reach up to 16 inches. There are other species in the Botia genus that remain around 4-5 inches, and there are the dwarf species someone mentioned already. Many of these are in our profiles, second tab from the left in the blue bar [you can click the shaded names for that profile]. Also many cory species are included.