Help With My Jack Dempsy's

[minnnt]

I have currently got 3 Juvi JD's of which i am hoping a pair will form. I think two have become fond of each other so i am hoping they can grow up together and be friends. The thing is one of them is black and the other is grey. Can anyone explain the reasoning for this? Are they different strains/genes or is it a sexing thing? Two are grey and one is black.

I have included some pics, but they are a bit blurry as they don't stay still for long enough for me to snap them.

Any help would be appreciated, cheers.

Also, the black one is way bigger than the other two but they were all the same size when i bought them.

Together:

Grey:

Black:

Thanks again, David.

 

[roadmaster]

I see from the first photo,two jack dempsey's and a firemouth.
Larger ,darker,jack dempsey is prolly the dominant fish and the other's simply not wishing to display vivid coloration in his,her presence.Will change as fish get older and or form a pair before spawning.

 

[minnnt]

You see correct... Thanks for your help. He doesn't show any aggression towards the other two JD's even though they are smaller.