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Hi Aquarists! I've had some white clouds for about a year in a low-tech pseudo-walstad tank. I started with two who happened to multiply; I now have seven. The largest one has been taken ill for almost a week now, and he has the following symptoms:

Tail appears irregularly bent near the leading edge of the anal fin.
Blackened rear half of body from dorsal fin to caudal fin.
Buoyancy - floats upward tail-first.
I noticed that some scales appeared to be lifting up slightly near the site of the bend.
Round white lump on dorsal fin
Hyperventilating

The above symptoms are listed in the approximate order that I noticed them, as they developed over several days until today.

I've seen a few different sources which all seem to have different ideas as to what it may be. Please advise. Image below. He is currently in a small holding container to protect his family in case it's communicable.

Thanks.
Could you possibly take a photo from further away as well, so that I can see this in the context of the fish itself?
I'm thinking that what you may be witnessing is the breeding tubercles on the male fish which tend to be evident at this time of year in particular, and you may notice them chasing the females too.
However, a photo as described would help to definitively work out if it's this or something else.

Also, can you provide liquid-based test results for ammonia, nitrite and nitrates in the water? Thanks.

Hi, my goldfish have been in a temporary tank of 980L for 6 months without any issues. We regularly clean the pump. There are 12 gold fish in there of various sizes. I have noticed that at least 1 goldfish has developed a growth on both gills, see photo, and it looks like some of the others are starting to get this as well. Any idea what this is and what treatment is available? Many thanks Alex

In order to help us to advise you, we really need at the very minimum:
* readings from a liquid-based test kit for ammonia, nitrite and nitrates [plus a history of recent readings];
* your tank maintenance regime;
* photos or the video clip you refer to.
Once we have this, we can then advise further. :)

I have recently become the owner of 2 lovely little fish after the previous owner moved away (neighbour had just left tank and fish outside to be taken for free with the rest of unwanted furniture)
I've never owned fish before and have no idea what these guys are even called . I've got them in there original tank and done a water change , around a quarter of tank water .
Any advice on what they are and best way to care for them would be appreciated

I set up my tank in late Jan and did a fish-in cycle.
It's a 60L planted (now) tank.
6 Neon Tetras
1 female Betta
11 shrimp (cherry and sunset orange, small)
4 Platy, 3 female I male. I had to take my original male back as he was aggressive. I asked the store for another female but ended up with another male, the current one.
He's white (see-through-ish) with a mottled back tail fin.
I got the new male approx 2-3 weeks ago. He was fine, but a couple of weeks ago I noticed a small white lump on his chin. He was fine so didn't think anything of it. Then last week he started swimming bizarrely, as can be seen in the videos. He got stuck inside the bogwood and I had to gently pull him out by his tail fin as I thought it best.
I am new to fishkeeping and have no idea what could be wrong or what to do about it. He doesn't seem to be eating and is quite skinny.

Thanks for the reply, I have an 125liter tank but am struggling to find a stand for it or a way of putting the fish tank safely onto my carpet, either that or I may have to put it in my hall where I’ve got tile floor, I put the aqua safe into the tank and have got a thermometer so I can check the water temperature, which is now okay, I think he may be happier in the 125liter tank as that’s the same size my brother had him in, the tank it’s in now is only 38liter but needed to take him as he was bullying the other fish he was with.

If nitrite is high that is why the fish is sick - it is being poisoned. Ammonia is also likely to be high but the test strips you have don't show it so how high is a guess - get an ammonia test ASAP. To help him you need to change enough water to get nitrite down to 0.25 or less. Use the Aquasafe to treat the fresh water before putting in the tank as this is essential to make the water suitable for fish. Your filter is not cycled, so the nitrite (and ammonia) will continue to rise meaning you will need to do water changes daily until they are consistently at 0.

Longer term, how big is your tank? I'm guessing quite small as that filter is for small tanks and isn't going to be adequate for a large goldfish. He will need around a 180-litre tank with an external filter to thrive long-term.

Hi thanks for the reply, I have bought tetra test 6in1 and it has shown the nitrates and nitrites are high, I have also bought tetra aqua safe to see if that helps, I’ve also bought some quick clear as the water is a little cloudy, I have got a filter that came with the tank, I’ve inserted a picture, I fed him this morning and he ate off the bottom of the tank and was swimming around a bit more.