I housed Porky in a 100 gallon tank. I fed him clams, mussels, shrimp, crabs, snails, crayfish, octopus, squid, krill, ulva macroalgae, and sometimes other fresh/frozen/freeze dried raw sea foods. The brand doesn't matter, just the absence of preservatives. Just think of it as food instead of something that you buy that's labeled fishfood. Human grade seafood is so much cheaper, fresher, and higher quality than anything you'll buy at a pet store. You can even buy live clams and mussels at seafood counters in some stores. I also like to feed the mixed frozen seafood you can buy in some Asian grocery stores. It contains a seasonal mix of things like shrimp, prawns, crab, octopus, clams, and mussels. It's tasty for humans, too. Just read the label for preservatives and don't buy if a food uses any.