From what I have found in the net, there should be no problem. Just make sure, that the sizedifference is not too big. If You are keeping it with senegalis or delhezis, it should be all right, with ornatipinnis, endlicheri or other bigger ones, it will end up as food.
I believe I have a lapradie(Sp?) about 7-8". They said the Eels usual come in about that size, so hopefully they do. Then my Tangy Tank will be lookin good.
i only found 1 site (tropheus.info)with info on them so thats why I was trying to see if anyone kept them.