Help with bass

I have a redeye bass that is 7in right now. He use to be out in the front all the time and the first to eat, but now he hides all the time behind the amazon sword and doesn't eat. This is weird since he is peaceful, but doesn't take aggression from others. Now he darts for cover at the slightest movement. I did a water change yesterday and might again today, but nothing else has changed for a while. I also don't think it is the water change since this started days before it. What do you think is going on? I usually feed him Hikari food sticks, sinking pellets, and frozen bloodworms. Now he rejects even the bloodworms he use to do anything to get. Other than behavior, he looks normal.

I can test water quality soon.

What do you think I should do?

The very first thing I would do is perform a water change and add a tablespoon of salt for every 10 gallons of water. In case he is coming down with something, this should buffer his immune system. I would also check if there is any stray electricity getting into the tank.

I  will probably put him in a separate aquarium since I have a lot of plants and some scaleless fish that would be sensitive to salt. How often should I feed him while in the hospital tank?

What are the other tankmates? 

 

If you put him in a hospital tank, I'd offer food daily still. Just take out what he doesn't eat. 

Unfortunately not many natives. Here are some of the tankmates: Black ghost knifefish, Four-lined Pimelodus catfish, Beijiangensis Barb (Acrossocheilus beijiangensis), Chinese giant bitterlings, some T-barbs (also called spanner barbs), my Railway barb (Acrossocheilus fasciatus) and some other fish. I do have 2 creek chubs and a longear sunfish, but with the price of shipping, my options for natives are severely limited. All of these fish are in about 72 degree water and are happy. no one ever fights except for the occasional "fight" between 2 barbs. The railway barb is probably the only one that chases fish occasionally because it can be territorial sometimes.

so the bass is not really better or worse. he is eating and can swim again, but he sometimes swims upside down and flips sometimes. 

Can you get a video of that? How long does he swim upside down?
That could be a number of things. It's good he's eating, but there may be some sort of swim bladder issue. I've also seen fish that get spooked, nail the side of the tank and just have neurological issues from it that makes weird swimming behavior.

I think the best move is to put him in a hospital tank, salt him up to about 5 ppt and hit him with some general medications for internal parasites or something similar and see if there's improvement.

What have you been feeding him? Does the fish appear to be bloated? It sounds a bit like dropsy.

I've been feeding mostly bloodworms while he is in the hospital aquarium, but I did feed 2 small hikari carnivore floating pellets. He does not look bloated. I added some salt to the hospital aquarium 3 days ago when I first set it up.

I put him back in the 150 gallon on sunday because he seem to have at least his energy back. He was still acting strange, but was back to normal for the most part. Yesterday he started eating the pellets again. I think he is almost 100% back to normal. 

Thank you for all the help.