That's a good idea. But one word of warning: Pacu are very, very fast fish when they want to be. They can zip from one end of a six-foot tank to the other in what seems a split second.Fried_fish said:They should be fine but with fish there is nothing 100% I would provide some hiding space for the loaches if you decide to mix them.
The tough part about putting a Pacu and a Clown Loach together is that CLs grow very, very slowly and Pacu grow very, very fast. So there's going to be a signficant size diference for almost the entire lives of both fish.
Chuck