big sigh........ your extremist point of view is exactly what landed the OP with a 55g and his current stock. If all he hears from the LFS is "1" per gallon" and all he hears online is "you need a 300g tank" hes not likely to take your advice seriously (and he shouldn't) this is exactly what nc nutcase has been saying, people on this forum shout random crap without any evidence whatsoever to back it up. and it always results in a disservice to the op and his fish.
no he does not need a 300g tank and he's not going to and shouldn't take your advice. You're some random dude on a forum telling him "anthing less than 300g results in dead fish" when he's already got them in a 55g and they're obviously not dead.
I mean surely my 100g with it's RD and 2 JD's must have 2 dead JD's in it by your logic; which it obviously doesn't. Post your reasoning and your experiences and you may be taken seriously. Right now you look like a random extremist who wants everyone to spend 5000$ caring for 30$ of fish. I mean what's next? "no one can keep a molley alone in anything less than a 100g" ?
@ the op, shoot for a standard 125 and you'll be fine. Just add some nice driftwood and decoration and they'll find their own territories.