Red mark on tail

[Charlotte-47]

I hope the picture has attached.

My goldfish has this red mark on his tail, can anyone advise what it could be please and what I need to do. It appeared a couple days ago and has got noticeably bigger. Thank you.

I did a water test yesterday-
Ph -7.6
HR Ph- 7.8
Ammonia 0ppm
Nitrate 0ppm
Nitrite 0ppm I will test again in a minute.

Info - Tank is 200L, two large very old goldfish, last water change 4 days ago 50%. Tank has Fluval filter and airstone. Both fish are eating and their habits are the same. Tank hasn’t changed, been set up for years (fish moved house a month ago but all filter medium, water etc came with them) . Water change 50% once a week.

 

[Aiken Drum]

Id say septicaemia, but see what other people suggest.

 

[Charlotte-47]

Thank you for replying.

If it’s that is there anything I can do and is he suffering? What could have caused it? I really don’t want him to be in pain.

 

[Andy Sager]

Confirm that there isn't a thin black line coming or anything sticking out from the red area on the other side of the fish that's pictured.

 

[Charlotte-47]

There’s no line or anything sticking out of it. Both sides look the same. What would those two things indicate?

 

[Andy Sager]

There’s no line or anything sticking out of it. Both sides look the same. What would those two things indicate?

Anchor worm is the most common one or another type of parasite. If there is no damage to the skin and just the bloody spot inside, the fish may have suffered an injury during the move you mentioned took place a month ago. Clean water and the addition of some aquarium salt would help that.

If there is a rupture of the skin or the redness does not respond to the clean water and salt, the best treatment would be to isolate the fish in a hospital tank and treat with an antibiotic to counter any bacterial infection. The correct medication for this based on your Ph would be Kanamycin ( Kanaplex) or Doxycycline only if you have a low GH. Doxy does not do well in high calcium environments so you would use Kanamycin if your GH is high.

 

[Charlotte-47]

Thank you so much for the advice.

I’ve just had a good look and there’s no cut or obvious wound to the skin. It is definitely inside/under his skin and he has no other marks on him. Should I do a 50% water change early? (It’s due on Wednesday) and please could you explain about the aquarium salts? I could get some on Tuesday.

Sorry - Edit to ask if it was a wound when I moved them would it have shown up before? Or would it be normal for it to take a month? I’m really hoping it is an injury as although that would have hurt him it would be less painful that anything more serious. It looks like it has little dots inside the mark if that means anything?

 

[Aiken Drum]

Kanamycin ( Kanaplex) or Doxycycline

From previous posts and OP quoting tank volume in litres, safe to assume they arent from US, so these antibiotic medications are likely to be vets prescription only. Probably the most effective antibiotic medication available here in the UK would be myxazin, and i would never put that in a display tank because it stains everything green. After myxazin, maybe Esha2000 but I dont see that treating anything other than minor infections.

 

[Charlotte-47]

Aiken Drum, I am from the UK. Do vets here give prescriptions for fish? I’m sorry for all the questions.

Could you advise me on how to use the aquarium salts please? I remember using them years ago but have forgotten so much and don’t want to google as it’s not always right.

 

[Colin_T]

It's either the start of anchorworm or a blood blister. It's unlikely to be anchorworm though because you have had the fish for a month and nothing new has been added to the tank.

At this stage clean water and salt (as recommended by Andy) would be my suggestion too. Give the tank a clean before you add the salt. Wipe inside of glass, do a big water change and gravel clean the substrate. Clean the filter if it has established otherwise leave it for a few more weeks.

------------------

SALT
You can add rock salt (often sold as aquarium salt), swimming pool salt, or any non iodised salt (sodium chloride) to the aquarium at the dose rate of 1 heaped tablespoon per 20 litres of water. If there is no improvement after 48 hours you can double that dose rate so there is 2 heaped tablespoons of salt per 20 litres.

If you only have livebearers (guppies, platies, swordtails, mollies), goldfish or rainbowfish in the tank you can double that dose rate, so you would add 2 heaped tablespoons per 20 litres and if there is no improvement after 48 hours, then increase it so there is a total of 4 heaped tablespoons of salt per 20 litres.

Keep the salt level like this for at least 2 weeks but no longer than 4 weeks otherwise kidney damage can occur. Kidney damage is more likely to occur in fish from soft water (tetras, Corydoras, angelfish, Bettas & gouramis, loaches) that are exposed to high levels of salt for an extended period of time, and is not an issue with livebearers, rainbowfish or other salt tolerant species.

The salt will not affect the beneficial filter bacteria but the higher dose rate (4 heaped tablespoons per 20 litres) will affect some plants and some snails. The lower dose rate (1-2 heaped tablespoons per 20 litres) will not affect fish, plants, shrimp or snails.

After you use salt and the fish have recovered, you do a 10% water change each day for a week using only fresh water that has been dechlorinated. Then do a 20% water change each day for a week. Then you can do bigger water changes after that. This dilutes the salt out of the tank slowly so it doesn't harm the fish.

If you do water changes while using salt, you need to treat the new water with salt before adding it to the tank. This will keep the salt level stable in the tank and minimise stress on the fish.

When you first add salt, add the salt to a small bucket of tank water and dissolve the salt. Then slowly pour the salt water into the tank near the filter outlet. Add the salt over a couple of minutes.

 

[Aiken Drum]

Aiken Drum, I am from the UK. Do vets here give prescriptions for fish? I’m sorry for all the questions.

You would have to find a vet that deals with fish and exotics. If they dont do house calls, find a container to take it to the surgery. Pay for the vets appointment and pay again what is probably £100+ for the medication.

You can import these medications online, but you risk impoundment and then fines for trying to import controlled medications.

 

[Charlotte-47]

Thank you so much Colin for the reply. I’ll do a big water change tomorrow and then follow your instructions with the salt on Tuesday.

I really appreciate everyone’s help, having the fish is constant anxiety about whether they’re happy and healthy so it’s a real help that this forum is here.

 

[Charlotte-47]

Aiken, I will try the salt and go from there. Over the years I had a vet out to pts fish that were really unwell, one had dropsy. (I’ve had 5 fish in the twenty years) They came to my house to do it and I’d find the money as I couldn’t have done it but obviously actual treatment will be far more going by what you’ve said. Hopefully the salt will work.

 

[Andy Sager]

Thank you so much for the advice.

I’ve just had a good look and there’s no cut or obvious wound to the skin. It is definitely inside/under his skin and he has no other marks on him. Should I do a 50% water change early? (It’s due on Wednesday) and please could you explain about the aquarium salts? I could get some on Tuesday.

Sorry - Edit to ask if it was a wound when I moved them would it have shown up before? Or would it be normal for it to take a month? I’m really hoping it is an injury as although that would have hurt him it would be less painful that anything more serious. It looks like it has little dots inside the mark if that means anything?

Colin and Aiken have answered the medical part of your question so I'll address the physical. It's possible that there was a minor injury during the move that just took time to get worse. Goldfish also like to dig in the gravel with their tails so it may not have been from the move but from a recent activity. If the spot has been growing over time, it's more likely from the move but if it wasn't there yesterday but is there today, it's a fresh condition. The fact that there is no ruptures in the skin is a good thing because it means no access for bacteria in the aquarium to infect the wound. That said, "blood blisters" can also be a sign of high ammonia and that too could have happened as an aftereffect of the move or an internal bacterial disease.

I'm not familiar with medications available in the UK as Aiken would be but to treat this if the salt and clean water does not work would require an antibiotic that is absorbed through the skin or administered in the food. This is not something that can be treated with medicines that are only for external issues.

Hope this helps.

 

[Aiken Drum]

Aiken, I will try the salt and go from there. Over the years I had a vet out to pts fish that were really unwell, one had dropsy. (I’ve had 5 fish in the twenty years) They came to my house to do it and I’d find the money as I couldn’t have done it but obviously actual treatment will be far more going by what you’ve said. Hopefully the salt will work.

I agree with this. Im not suggesting you go to the vet at this stage, just pointing out that the kind of antibiotic medications suggested isnt readily available here. I actually dont think the antibiotic medication available here is much use to treat anything serious. If you are going down that route though i would agree with medication mixed in with food is probably the way to go. We can look at that if we get to that stage.

What id be concerned about would be going to the vet, and they go with over the counter medication because its easy and available. And then you have just wasted a lot of money. I would be really interested in what a qualified vet had to say though and what kind of medication they would actually prescribe.

For info, and future reference. Im also hearing whispers that what antibiotics we do have access to might be controlled in the near future. Malachite green (the active ingredient in myxazin) is something i understand they want to control as people are using it on themselves.

 

[Andy Sager]

Here's a site in the UK that might be of some use to you and the others there. https://fishdoc.co.uk/ The site is about koi but goldfish fit that general category.

 

[Aiken Drum]

Here's a site in the UK that might be of some use to you and the others there. https://fishdoc.co.uk/ The site is about koi but goldfish fit that general category.

Weird that. I was just on this same website.

The site says that malachite green is expected to be banned from fish medications in the near future. Followed a link to practical fishkeeping, and its already banned in germany where they are now having difficulty controlling ich.

 

[Colin_T]

You can treat white spot with heat or copper. Praziquantel might work too. Acriflavine and triple sulpha might work (separately, not together). If worse comes to worst, move the fish into a clean container every day for a week.

Malachite Green (aka Victoria green) is a carcinogen (causes cancer), so it's good to remove it from the market, and bad for people to be using it on themselves.

 

[Charlotte-47]

Here's a site in the UK that might be of some use to you and the others there. https://fishdoc.co.uk/ The site is about koi but goldfish fit that general category.

Thank you, I will have a look at that site.

 

[Charlotte-47]

I know absolutely nothing about the medication but would go by advice on here rather than a general vet. I am going to see if there’s an actual aquatic vet in my area but would only use if there was signs of him suffering.

If it’s serious would he be showing signs of ill health? He’s swimming around happily as usual and asked for food as soon as I went in this morning.

I’m concerned that I no longer know enough about how to keep them in perfect tank conditions.