well you're probably not going to like my response but here goes: your fish may be small right now but as they grow to sexual maturity you're going to end up with many fewer fish than you've got in that 55 right now. texas and red devil cichlids are extremely pugnacious and will very likely shred the rest of your fish. your hemichromis is also a beligerant sort and will happily kill off the other fish. those fish need a 150 gallon tank in order to live amicably together and frankly, even then i think you'd have some problems. and finally, corydoras are actually a 'shoaling species' and do much better with 5-6 buddies.
you cannot simply dump a bunch of incompatible cichlids in a small tank and expect them to thrive. do some research on the mature size of the fish you expect to keep and their compatibility issues and tank size requirements before you buy them and both you and your fish will be much more successful in the long run.