Yes, oscar fish can eat mussels. Oscar fish enjoy eating small fish, insects, and invertebrates, and seafood, such as mussels, can be a wonderfully nutritious addition to their diet. Just make sure the mussels are prepared without salt or vinegar.
Aside from mussels, here are some excellent food recommendations for your oscar fish:
- Fish flakes and pellets
- Freeze-dried bloodworms
- Brine and krill shrimps
- Chopped up vegetables and fruits (remove the seeds)
Make sure to source the live foods properly. Only buy them from reputable sources to avoid introducing diseases and parasites to your oscar fish. If possible, try farming them yourself.