what is a good diet for oscars??

I agree, start feeding them pellets/food sticks at an early age...this is the best staple food for any oscar...you can suppliment it with earthworms, shrimp, feeder fish(make sure they are disease free), and crickets(a favorite)..I used to gut pack my crickets with flake food.
 
I usually just bought the crickets in bulk(several dozen) and kept them in a 10 gallon tank with paper egg carton and cricket quencher(a gel-like water source)..."gut packing/loading with flakes".... just pour some fish flakes in the cricket cage in a dry spot and the crickets will devour them....getting quite plump in the process. When your oscar eats them, he will also be getting some healthy, vitamin enriched fish flakes.....my oscars absolutely went nuts for them.
 
I have made a puree in the blender with beef heart (from the butcher at Publix) Ocean Nutrition formula two algae based flake, cichlid stix and frozen spinach. I then put it in a ziploc bag and froze it and broke off chunks like it was frozen food and fed it. My oscar loved it. Chili- I think you are not supposed to feed pure beef heart because heart is a muscle and is very high in protein but lacks vitamins.
 
Beefheart supplies Protien which is a very important factor in juvinile fishes growth and it also supplies Iron which is important for strong skeletal structure. Also I have always believed that just a variety of foods on a daily basis is as good as any pellet with vitamins that are not natural. I feed my O's this mixture Shrimp, Scallops, Beefheart, Lobster or Crab on occassion Earthworms, Grasshoppers, Silversides, and extra lean ground beef I fell that with this mixture the will get the vitamins neccesary.
 
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