I feed mine New Life Spectrum pellets, Veggie Flake, Omega One Cichlid Flake, Frozen Brine Shrimp & Mysis Shrimp. Live brine Shrimp, once in a blue moon live black worms.
I avoid bloodworms for various reasons.
I avoid Beef Heart, fish are cold bloodied & cannot assimilate fat from warm bloodied animals. Therefore it is stored in tissues, especially the liver.
{I know people will say they have done so... blah blah blah. Just stating a fact & with what is available why take the risk. Good luck, well done etc to those that do.}
Frenchy