Hi folks, ok, typically I was feeling all chuffed as my tank has been nice and balanced for a good 6 months now, when I went & forgot to plug one of my filters back in after the last waterchange...! Doh :(
I noticed it 12hrs later & plugged it back in and dosed with bacteria, and fortunately I have 2 & the other one was still running at least, but it is now apparent that it has caused some upset, as, even though testing hasn't actually shown a terrible increase in undesirables, one of my Rathbun tetras now has a whitespot on the tail.

The strangest thing is that one of my White Clouds has suddenly developed a bubble-like blister on its lip. I've never seen it's like before, and I can't find anything in any of my books about it, so I wondered if any of you may have experienced something like it & know what it is? I'm thinking it's probably a bacterial infection or something, maybe? I've attached a pic, but it's so hard to get one clear enough to see how transparent the bubble is - definitely not a fungus anyway.

I have done another 15L waterchange (~90L tank) and dosed again with bacteria, but do you think I should medicate at all (I have WS3 & Melafix in stock), or should things just improve again if I keep up the maintenance? What do yous reckon?

Cheers,
Jess

The pic is a little on the small sisde but yes, my dwarf neon rainbow presented with what at first loked like a bubble/blister on their lip.

As it progressed other symptoms (see link below) started to show. I my case it turned out to be columnaris

link here: http://en.wikipedia.org/wiki/Columnaris

Gram negative bacteria that can only be treated with antibiotics. Are any of the other fish showing any signs of this? Can also be triggered to stress (overcrowding etc) so wise to rule that out too.

Ah... Oh dear, not what I was hoping to hear! Columnaris sounds nasty indeed, we've never had that before :( Thank you ever so much for your rapid response though!

I think perhaps one other minnow also has a slightly suspect lip, looks a bit too white & a touch swollen maybe. So, perhaps it would be wise to medicate indeed, but I have to admit I'm very wary of using antibiotics - don't they knock the filter out as well?

There are 10 minnows and three tetras in my 80x40x30 tank, and they've all been happy and stable for several months previously, so I guess I'd be surprised if overcrowding was the issue, but I would defer to your opinion on that! There should be more tetras, in another tank, I know - just haven't been able to make that happen yet, but so far they seem to have got along pretty well really, although 2 did die early on. That's another story though!

Sorry about the previous pic, it did look bigger in the preview! I got another one just now anyway, will try that! Seems like the blister has got larger, but so far the fish appears totally unaffected by it. Troubling anyway, but you don't think Melafix or the Malachite Green in King British WhiteSpot3 would help at all...?

Do you either make water changes using some cold water or top up the tank with cold water?
This looks very much like gas bubble disease.

As Violet says though anything unusual on the lips/mouth could easily be the beginning of a columnaris infection.

Does the affected area have a texture or is it completely smooth like a blister?

Ooh, that sounds like a possibility, maybe...! It is an absolutely smooth outline, shiny & increasingly transparent, just like a bubble/blister and not fuzzy at all.

I fill a 25L bucket with straight cold water using a shower head, then add de-chlor and leave it to age for a number of days - in this case it had stood for 3 days. The temp went from 17 (fresh from the tap) to 19 (when I used 10L for that waterchange), and the tank at that point was 21. I usually do 25L change but got interrupted on that occasion so cut it short, which is also why I forgot the damned filter! However, thinking about it, I also left the water level a bit lower than usual & so there has been more surface turbulence than normal!

I have aerated more at other times and nothing untoward has ever happened, but there's a first time for everything eh? I just searched for gas bubble disease and there's one pic of a Danio with a bubble over its eye that looks extremely similar indeed! Seems so obvious now, but I suppose I've been lulled into a false sense of oxygenation-security, so to speak...

So, poor little minnow!! What have I done to it? It looks like it might just burst any moment! I did 15L waterchange earlier today and topped up the level so the filter outlet's not aerating nearly as vigorously now at least, but I must read up a bit sharpish on what else to do for the best - if you know please feel free to give me a quick version!

I have wondered whether my room-temp waterchanges are close enough to tank temp to be safe, usually 1-2 degrees cooler, what do you reckon? It hasn't been a problem over the summer, but maybe now things are cooling again... I need to discus my heater situation I think!

However, right now I'm going to neb up on gas-bubble disease, but thank you SO much for the suggestion!!

Hi Violet & finnipper, thanks so much for your input yesterday. I did a bunch of reading on Columnaris & Gas bubble disease, and I have to admit it is jolly confusing! Especially about the specifics of turbulence, de-gassing & whatnot... There's also the possibility the bubble could have been caused by an infected wound, but it didn't really look affected enough for that to be the case I think.

I find it very difficult to be certain what my conditions actually are! It's all so relative & without seeing exactly how other people have their tanks I'm just not sure. I did an O2 test (JBL) on the 95L tank & a tiny nano I have also, and they both seemed to read about 8 mg/l, but that is one of the trickier ones to compare on the chart properly, so I'm never quite certain!

Anyway, the good news is that after looking bigger than ever last night, this morning the blister seems to have almost completely gone! Yay :) I guess hopefully whatever I did do with the filter outlet & waterchange yesterday has helped...? I think it looks more like the bubble has been reabsorbed than burst, there's no raggedness or apparent damage, just a slight white bump now, and also the spot on the tetra seems to have dissipated somewhat too. So, fingers crossed that's the worst of this episode behind us for now... (Prays!)

I'll be keeping a sharp eye on the situation anyway, but thanks again for giving me a clue.

Cheers,
Jess

Glad to hear it has improved. Thanks for letting us know.

No worries, I do think it's useful to know how things develop after these emergencies, for future interest maybe.
Cheers again for now anyway