Kinda hard to tell because they're juvenile, still got their stress colours on a bit and the blurring on the tail further complexes the identification!
However.. he looks like the same species as the picture that I showed you the other day, in the other thread.. which is a fish I still haven't truly identified - just presuming it's one of the undescribed species from the Geophagus sp. "altifrons" complex.
Either way mate they're going to turn in to a gorgeous fish. However.. I would say.. get him on a power feeding Frozen foods twice a day for as long as you can keep it up - looks a bit thin!
Take some more pics in a fortnight and maybe I'll be able to help you a bit better then. Sorry
In the wild their natural habitat would be sand substrate, with leaf litter and tree roots in the water. To replicate this I tend to just use sand and lots of good bits of bog/mopani wood. You can use leaves too, as long as they're the right type [I forget which] but I tend to find they just become a pain in the a**e after a while.. They won't need any caves, especially if you consider that these guys should reach almost a foot TL...
pH wise their natural habitat will be 5.5 to 6.5, though they can live in 7. I'd try and make your water more acidic if possible.
Yeah, hoy some peat in a filter net or a tight/stocking, put it in your filter and watch it stain the water. Your fish will appreciate it muchly and it will hopefully make it a little bit softer and more acidic