Whole prey items are best. You can hack up a fish (if it's too large) , but give him the whole fish and not just chunks of meat. but some good items include rodents, shrimp, crabs, fish, roaches, superworms, crix. the thing about fish is not feeding petstore goldfish/feederfish. they are kept in tight, unsanitary conditions commonly and are not a very clean food source. a mouse is a bigger and cleaner meal for the same price as a dozen feeder goldfish anyhow. as far as turkey burger, canned monitor food and eggs(unfertile chicken eggs from grocery store).... they are ok in a pinch, but don't let those items be anything more than an occasional feeding. i feed finger mullet that i net (benefit of living on the water in Florida) to my larger monitors. be creative with where you live, but think whole animal feeders, not chunks and bits from the grocery store.