Regarding someone's earlier post, red wolfs won't get 20 inches long. Perhaps you thinking of the Mala wolf.
I got my red wolf with a red severum, rainbow shark, and blue acara. It's crazy cause the rainbow shark could totally fit in his mouth but he completely ignores him. The only time where there's trouble is during feeding time. I try to grab the attention of the wolf on one side of the tank and the other fish on the opposite side when feeding dry food. And when I feed tilapia or shrimp I give my wolf a big piece and he won't bother the other fish when his mouth is full. I don't feed live food other than worms, dry food is nls Thera a, massivore, and omega one veggie rounds (I try to target feed my severum this but my wolf will eat it too). Frozen foods are tilapia and shrimp.
If you go down the polypterus route just make sure is around the same size as your wolf. My friend had his with Senegals and he witnessed the wolf easy one during feeding time. The wolf was going for a pellet and the Senegal ate it before the wolf can get to it, then the wolf stuffed the Senegal in his mouth and made a quick meal out of him. I was doing research before I got my red wolf and a lot of people have had successes with polypterus as tank mates. I have a polypterus tank and think these are awesome fish to keep.
I currently have 2 wolfs (Mala and red wolf) and from my experience I think many plants (fake or real) and a hallow wood or a cave is a must to have in your setup.
Have you thought of just keeping a purple wolf on his own? When mine was in quarantine on his own I noticed he was more active vs with tank mates.
Good luck with what you decide. Red wolfs are awesome mini monsters!
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