I don't know what's wrong please help me

[HelpPlease01]

I have 2 fishes.

One is completely fine. The other one is not.

The one who isn't looks like he's full of air. He's not looking like a balloon or anything, he looks normal-ish, but turns around as if he had air in his stomach, and that "pulled" him up.

He swims weird, on the side (happened maybe 3 times in the last 2 weeks?)/upside down (really rare, happened only once and i caught it on video)/and has started to hang out at the very top of the tank, sometimes without swimming (but if I gently tapped the glass or passed my hand on it, then he would immediately move normally, like he's waking up from a nap) + Even if I'm not giving them food (general flakes for fishes from the store) he keeps gaping at the surface, trying to eat nothing/the bubbles made by the pump.

The other fish doesn't do any of this, he hangs around everywhere, eats normally, hides in his favorite rock, the fish-ish stuff fish do.



I'm putting the video as attachment.

 

[GaryE]

I don't have any good news, I'm afraid. A fish has two gas bladders on each side of its spine. They draw air from the intestines, and maintain balance. Your fish has an internal problem that's interfering with the swim bladders. Usually, that's an infection, but it can be a blockage, an injury or a genetic problem. Once the fish has completely lost its equilibrium like that, recovery is almost impossible.

Goldfish produce a lot of waste. Are they new fish, and is the tank "cycled"? If not, look that up.

Do you do regular partial water changes, with a water treatment for chloramines or chlorine? Your healthy fish was gulping in the video, so I'm wondering if the water's off.

Try not feeding them for several days, and see if that helps. Overfeeding is common with newish fish, and that can contribute.

I hope it works out.

 

[MattW]

Probably not related to this fish's issue, but I read that carp species incl goldfish, can be prone to swallowing air when feeding on floating foods (leading to floating issues). It was reccomended quick sinking foods or pre-watered-down flakes would reduce the chances of this happening.

edit* Just saw the full vid and noticed the other one gulping at the surface for a moment. More likely a water quality issue imo. What size tank do you have them in?

 

[Innesfan]

edit* Just saw the full vid and noticed the other one gulping at the surface for a moment. More likely a water quality issue imo. What size tank do you have them in?

Yes. Check water values. It looks like things have gone bad water quality-wise. I assume you used a dechlorinator.

Also, as @MattW, suggested, for goldfish, pre-soaking dried food, flakes and pellets, is a good idea. Even better is not to feed dry food exclusively. I feed my goldfish frozen foods and lots of green foods--par-boiled peas (pop them out of the skin), broccoli, spinach, the occasional dollop of cooked oatmeal, a few grains of boiled rice etc.