Are all these cichlids housed in the same tank? The Africans (2nd, 3rd, and last pictures) have different water and food requirements than the others. The Oscar will also get much larger than the others and possibly eat them or kill them.
The Oscar alone would stock the tank. I'd get atleast a 75g for him alone. I'd also take the Convict or Parrot (whichever it is) to the LFS. Either that or take the Africans back. You shouldn't keep them together.
The Africans (specifically Malawians) need a high pH and need some veggie matter in their diets. They shouldn't be mixed with the Oscar and the Convict or Parrot.
I also have black convicts and they are african cichlids and they don't bother each other. The oscar is pretty good in the tank he really don't bother anybody but the electric blue johanni ( i think) picks on the oscar sometimes. Whoever wrote that those 2 little ones in the last picture were clombian sharks i was told that they were siamese iredencent shark catfish and they only grow to 4 to 5 inches big! all those fish that I have pics of on here were givin to me when i bought the 55 gallon from someone I have a seperate 29 gallon tank with one mamma convict and about 30 fry i had 2 clown loaches 2 of those catfish i was talkin about and 2 juvinile black convict, and a red tailed black shark and they all got a long no fighting at all. but I moved all of those into the 55 gallon so the fry wouldn't get ate because mamma had all the fish in one corner of the tank. Ever since I moved them all the red tailed black shark disappeared but all the others are getting along