Rainbow With A Swollen Belly

When I was restocking my tank a couple of years ago, dwarf rainbows were one of the contenders so I read up on them. I came across several sites saying that this species is prone to ulcers. Does the wound on your fish look anything like an ulcer? I have found a few comments that the main cause of these ulcers is feeding the fish too much flake foods which are rich in protein and fat. Food such as small crustaceans, fruit flies, bits of fish and algae & courgette seem to be better for rainbows in general.

As for the wound/ulcer, you could try eSHa 2000 or Myxazin in a separate tank. They may not cure the would but they should stop secondary infections. And since rainbows need big water changes, a few 50% + water changes a week on the hospital tank might also help.

Yes, this looks rather like what my female x-ray tetra had ie an ulcer which ultimately became repeatedly infected and finally led to her demise. It started off small, when I really ought to have removed and treated her, but for various reasons didn't. I'd advise TLC-ing the QT and nipping this in the bud over the weekend through the medications suggested by Sue.

What is the difference between Myxazin and Myxazin P?

Ah, ok. I just need to normal one then? Otherwise I'll be putting tiny amounts in my 25l aquarium!

New betta tank hospital tank is all set up. Albeit without mature media, plants or poorly fish.

I know it was a long time ago, but my first ever tank catastrophically cracked during set up (pre fish, thank goodnes). So I'm just being a little bit wary and would like to run the tank, heater and filter overnight before I put a poorly fish in. I don't want kill him when I'm trying to heal him!

I thought the wound is looking better today, but he is not behaving well. I hope he lasts till tomorrow and that I've not left it too late.

Best of British (and French) with the poorly dude H... 

Good job I left the tank running overnight. The heater definitely works. But I set it way too high. Tank was 30°C this morning. My poorly rainbow would've cooked if he's been in there!

Fortunately with 25l a quick 50% water change, with cold water only has appeared to bring the temperature down to 24°C, which is where I want it. Need to let it resettle for a couple hours.

I've only had mine a few months - I bought them at the end of January. They haven't fully grown yet. But the one that is poorly was the largest of the males and is now almost the smallest.

As @Sue mentioned earlier, I also read that they don't do well on dried food. So I had originally thought that was the issue (especially when it was the largest and greediest rainbow that was suffering) so I've been feeding a lot of frozen and gel foods recently.

I'm starting to suspect that the rainbows will need non-dried food more than once a week and am trying to work out what the best food routine will be for them.

What did you feed your rainbows, @daveyng ?

So the poorly rainbow is in the hospital tank with myxazin, a couple of floating anubias and as much filter media as I could squeeze inside the foam.

He made little protest about me catching him and putting him in a jug. And actually seemed less poorly once in the hospital tank. He's not staying as close to the surface, he seems happy hiding under and behind the annubias.

When I was at the fish shop, buying the myxazin, I also got some black / blue backing. Because of the way it curls and the tank is actually lifted up a bit (it is described as floating) I've been able to just 'wrap' the backing over the back edge and the top and bottom of the tank at the back.

The wound and the swollen belly look better today, but his behaviour is more that of a poorly fish than it has been to date. Here's to hoping this helps.

Should I feed him while he's in the hospital tank? I definitely don't want to feed him flake, but would he be better off on a total diet?

I couldn't decide yesterday whether the rainbow was looking better or not. Turns out it was the latter as he died overnight.