kribensis + ?

I don't think the combo your lfs suggested will work. Its not a matter of mixing new and old world. Kribs and Jewels are Old world, but need the same diet and water conditions as SA cichlids. FM are Central American and prefer a slightly higher ph. But all will adapt to whatever your conditions are. The problem is that the tank is too small. FMs get around 6in and jewels I think get the same size. None of them will tolerate another cichlids if they feel they are the "owner" of the tank.

You could do a species tank with any of the fish. Keep a m/f pair only, and in the case of the larger ones make sure you have a ton of hiding places. Being a confirmed cichlidiot myself, it stinks that you can't keep multiple species in a single tank, but with most non rift lake cichlids you can't. I see posts all the time with multiple species of med/lg Sa/Ca cichlids, but in my opinion, they are playing with fire and one of thier fish will eventually get burned.

If you keep a pair of kribs, then you could keep a school of tetras and a few other carefully selected fish, or if you must keep multiple cichlids in that tank, then do a Lake tang biotope. Make a reef on one side, and open sand with a few shell on the other. Put in a pair of small julies and a pair/trio of shell dwellers.

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