What's wrong with my American Bullfrog?

[Gemini]

So, the past summer I got my american bullfrog (Charming) from an Asian market. I know what he is by research on the internet but I have no clue how old he is. I have him in a ten gallon tank. It's a little under half filled with water and it has a lily pad thing he stands on. It also has a filter. I know I should get him a bigger tank - he seems a comfortable size for the tank, but I heard bullfrogs like bigger tanks. Anyways, this past week and a half he has been acting strange. I fed him night crawlers, I always have, he always ate them. I make sure to feed him every other day. Since last week, he hasn't been eating. He hasn't even been touching his food - whenever the worm is near him, he kicks it away. Things have gotten stranger. Now, occasionally, he closes his eyes. Now, I've only had him for like six or so months, but in that time I had him, I've seem him close his once. ONCE! He's doing every day now, every time I look over at his tank, that's what he's doing. I poke him just to make sure he's alive. Also, when he's not closing his eyes there is some white film over it.

I'm not going to pretend to know much about bullfrogs. I don't. I'm hoping that whatever he's going through is natural and he'll start eating again soon. But I'm worried. How long can bullfrogs go without eating? What we had was good, he didn't complain. He ate, croaked occasionally and swam around in the tank. I'm not sure if its my doing or not. I just want him to get better. Anyone have any suggestions?

[Thevacantface]

I have been looking into things that aren't clearly outlined in the care guides after the tragic passing of my Pyxie frog last week. Assuming all you parameters are in order for a healthy frog, you should check your water quality. Especially if the frog is trying to digest a large amount of food, it will be dumping lots of nitrates and ammonia into it's water. If they aren't being removed, it may be causing a toxic reaction to your frog.

[Gemini]

Sorry that happened to your frog.

I'm not sure what you mean by "water quality". Am I suppose to fill his tank with a certain kind of water? I always used tap. I cleaned his tank yesterday and I do it about once a month. I don't do it so often because I have a filter...

Question, should I try to force feed him. Like putting him in my hand and trying to pry his mouth open. He bit me once before, so I'm not scared of him. I'm just worried that'll make it worse, whatever it is. I want to take him to a vet but there are none near me that does amphibians. Only cat and dog doctors. If nothing else changes, perhaps I should let him go? But its mid winter. I don't know, I just want to give him the best chance.

[Crispy42]

Do you have a water test kit like the kinds used for fish aquariums? This will tell you your water quality by showing the amounts of ammonia, nitrites, and nitrates that are in the water from decomposing waste. If you don't have a test kit, you can bring a water sample to Petco or Petsmart and they will test it for free (go to the aquatics section). You might need to increase water changes (even with a filter) to keep these levels down.

Tap water should be find as long as you are adding a water conditioner to remove any chlorine or chloramine from the water. If you haven't been using a product like this then I would definitely recommend getting some to make sure his water is safe for him.

I really wouldn't recommend releasing him, especially in the middle of winter. Plus releasing captive animals can wreak havoc on the natural ecosystem if they aren't natively found there. Even if the species is native to your area, he could be sick and expose wild frogs to illness or parasites that they are not prepared to deal with.

[Thevacantface]

Follow what Cris said, and start conditioning the water immediately, that sounds like it is possibly the issue. As for the quality, same thing, Cris is right. Even if the water looks clean, and the frog hasn't been in it long, it could still be toxic, you should change it every day, or test and treat it every day and change when it gets bad.