EPA is found in the fish oil, it helps with mood and brain function.
DHA is less needed but is still good for the brain. I think 3000mg of
EPA is a good amount but you will need to ask your doctor or professional for the amount. I don't think you can ever have to much. I am on 6 grams of fish oil but with only has 2grams of EPA in the 6 grams of fish oil i take. Its important to make sure your fish oil does not have mercury in it other wise you can get heavy metal poisoning.