My Oscar fish has a fat lip. He has for a few weeks. I clean the tank every two weeks. He lives with a rather large pleko fish, some orange belly fish (2) and a bunch of guppies (which he eats). How can I fix his fat lip? It's not getting better and knocks his jaw out of line. please help me help my fishy.

can you please post a picture and water readings for Ammonia Nitrite, Nitrate, and PH.

How big is your tank?

We do need a pic to see if this is a problem or normal for an oscar

I'd like to post better pictures, but it keeps telling me it's too big, too tall, too wide... It's a bit frustrating.

Another photo. I admit, they aren't the best pictures of Oscar but I hope you can see him well enough. (Or her, I'm not sure)

I'm not sure on the water readings, as I don't have a kit, but the tank is about 30-something gallons.

I think this picture best describes his issue. I'm starting to worry about him. He still eats like crazy, and every so often I see him eating a guppy. Could it be from a guppy bone?

your problem is water quality, an oscar needs a minimum of 55gallons. you only have 30 gallons with a heep of tankmates. you are going to need to show us water readings asap.

do a %50 water change in the time being

You really need to get a liquid water test kit. Those readings can really help a lot in taking good care of your Oscar....

Although his lip looks big I wouldn't worry too much as long as he is still eating!

this is a sick fish, can you take to your lfs to place him in a hospitol tank

I must admit, I've had guppies my whole life, never an Oscar. How can I change half of the water? And what water do I replace it with? Tap water, distilled? Are there any additives that I can use to help him? And what is wrong with him, is it a virus or like a fish cold?

Pretty fish sure are a lot of work. but they are worth it. Thank you everyone for reading and helping me. I want him to live out a happy and healthy life.

do you have water conditioner? , you put this in your tapwater to make it safe for your fish. they should sell some at your lfs, also like niki said- test kits are necessary