You may be getting more than you bargain for by keeping a pair of bocourti in a 125 (assuming you can find a compatible pair, even by growing out a small group). They max out at around 35cm and are more feisty than pearsei. I have a bocourti in each of two 210 gallon mixed CA communities. Both are around 5 inches, and they regularly challenge others in the tank. Their aggression so far hasn't resulted in any noteworthy damage, but that may come as they increase in size. I agree that C. nanoluteus are too small and peaceful to put in the same tank. Perhaps Archocentrus centrarchus, Honduran redpoints, or firemouths?