Okay,new at this,sorry. The convicts r in a 10 gallon producing feeders with the red & blue gravel.There is 1 pair. The pics w/ leroy, my female red ear slider were the first day i brought home the oscars. Leroy started eyeing them up & I got nervous & threw them into my other tankw/ the river rocks.Thought they looked lonely & went out & bought allthe fish mentioned above, minus the 2 oscars. After they grow out I will split them between the two tanks. As for the black oscar, really it's a red oscar, same 1 in pic 1, 2, & 3.He seems to turn nearly all black when comfotable.