New Era make a frozen food enrichment. Basically it's an emulsion containing the vitamins and minerals in the pellets. It's used with frozen food and also with the fresh fish etc used at the public aquariums. It helps when transitioning the fish from the wet fish diets to the pellets as the fish are used to the smell. Gut loading fish with the pellets will also help because it introduces the goodness of the pellets with the meat the fish is used to.
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