All depends on how aggressive your rays are towards other fish. I tried bala's w/motoro's, and as soon as I skipped feeding for a day I'd wind up with dead/missing bala's the next. The bala's were about 4-5" and the motoro's a 4-5" disc at the time. My flowers have never been kept with anything besides a couple tigrinus who were always larger than them, and I have been tempted to try some open water tankmates.