Do you think large freeze dried brine shrimp and pellets are a good diet? My Oscar gets booth and i think he is costipated.

a mixed and varied diet is far better than 2 types of food. Yes pellets are good and i think should make up about 60% of the diet as pellets contain most vitamins needed by the fish. you add meal worm,earth worm,grass hopper,bloodworm,peas,lentils. the last 2 will help with constipation. Peas are very good for this and are a good size to feed to Oscars.

What leads you to think its constipated. how much are you feeding. for a full grown Oscar its not really needed to feed every day.Lastly is its abdomen swollen. It could take a few days to digest a large shrimp.

not pooing much slight loss of apatite

i believe shrimp and pellets could not cause
constipation just like that unless you have
problems with your water parameters.

My oscars do lost their appetite whenever they
took one good size mouse (1.5 inches body size)
and will never take any foods for two days. but
once they are through digesting that mouse, gosh,
too much pooing that make my tank cloudy and will
come to the glass asking for more food again.

OK 1st thing to do is test your water and post results. Its surprising how much your water plays a part in your fish life. you will need a full test kit for ammonia,nitrates,nitrites,PH. This will give us a understanding of your fish environment. What size is your fish and if you can give details about your setup the more the better. oscars can go for wks without food, but this could be a early sign something is wrong. Its all to common for oscars to stop feeding and many die this way with no idea as to why. dont worry I think yours will be fine as its still eating. how much do food do you give, its easy to over feed as they just keep wanting more.))