What type of flowerhorn is this?

[BIG_ONE]

i love him! in the week after i posted this hes already bigger! but the black has been on him, and dosent really change so i doubt its stress, maybe his young colors and will fade later?? but i really dont care hes awesome.

Oh it is stress alright. It occurs mostly on young fish that isn't comfortable in their home. Let them adjust, and sometimes changing the color of gravels or bumping up the pH and such can make them more comfortable.