Only problem you will have is feeding. Pbass will out eat the rays and they will have a tought time competing. Pbass are pigs, but they are also fussy. Start the Pbass and rays out in a different tank just for a bit. Train the Pbass on smelts or something that floats. Train the rays on pellets and or shrimp. I did this for a long time with no issues. Both got fed and nobody got hurt!