In your post in Chit Chat you listed 5 Rams...
If you go with 5 males... each one will want to occupy about 2 square feet of floor space as his territory. So this means you will need 10 sq feet (in other words, a 6 ft tank, 1.5 feet front to back, which is 9 sq ft). This would also not allow much room for other bottom dwellers. Since they don't have mates and won't be breeding, they will be less aggressive toward other fish (not including other Rams).
If you went with 5 females... each one needs a cave to call her own that isn't right next to another females cave. This would give you the majority of your bottom space for other bottom dwellers. This way is much more 'practical' but the females are far less colorful (but since when is fish keeping practical?)
If you went with 2 pairs, each male would again require 2 square feet of floor space which would take up all of a 55 Gal, 1/3 of a 75 and a little less than half of a 125, and 1/4 of a 180. Personally this is the way I would go regardless of which aquarium you get.
Choices Choices Choices…………………..