midevils

While spreading batches of midevil fry around some tanks to dispose of them, something unexpected happened. I have fed my male umbee a couple small batches of fry before but last night when i released about 50 fry in his tank something different happened.. He did not go for the fry but instead...

So about 8-9 months ago I got what petsmart sold me as a red devil (my first fish actually yeah little bit of a noob here) now he/she is right around 5.5-6.5" in my 50 gallon (raised in a 20long until about 2 months ago) but doesn't seem to really be growing very fast...if really at all...is it...