Frozen raw Beef heart, salmon and krill used by US discus breeder Jack Wattley.

1 beef heart 2.5 pounds+, with fat
2 pounds Of fresh Salmon
10 ounces of Spinach
8 cloves of Garlic
6 ounces of Krill Meal
6 Multi-vitamin pills
6 Multi-mineral pills
6 200 mcg selenium pills (Selenomethione or Selenocysteine, not Sodium Selenite or selenized yeast)

Soak vitamins in enough water to cover them or grind in a mortar.

De-fat the heart, grind in a grinder.

Grind the salmon.

Mince the garlic finely. Best to use a garlic press so there are no big pieces of it.

Transfer to food processor, add krill, garlic and spinach, then mix into a firm paste.

Put into freezer bags, flat.

Break a piece off when frozen and put it in the tank.

Does not keep in the fridge, use frozen.

N.B. I have a lot of references for selenium chemistry and applications in biology and medicine, but didn't include them here as they're rather lengthy. If anybody is interested, just ask,