Veil-tail angel w/ fin rot

I need some more advice. 3 weeks ago I asked for help identifying what was growing on my veil-tail angel fish. I followed Colin's recommendation to use salt. So now it's the beginning of week 4 and the fungus will disappear for a day or so but then start coming back. What should I do now, the fungus isn't going away.

Here's what I've done so far. My tank is 137L, I added 7 tbsp the 1st week, then added 7 tbsp more 5 days after the 1st dose. I've done a cleaning and water change during this time, replacing the salt when I add water (with prime). I have neon tretras, corys, 1 other angel.

ammonia = 0 / nitrite = 0 / nitrate = 20

I've attached a picture from today.
Thanks for any advice.

can you post some pictures that are in focus?

is the fish eating well?

what other fishes are in the tank?

May I just politely say, 137L is too small for an angel let alone two. Unless you are planning on them breeding then they will be fine but that is if you are planning on breeding them. A recommended tank size is 55 gallons for angels (220L)

Colin_T said:

can you post some pictures that are in focus?

is the fish eating well?

what other fishes are in the tank?

Click to expand...

Here's 2 more pictures from this morning. He seems to be eating well and acting normally. The other fish are 8 neon tretras, 10 corys, 1 other angel.

I need to do a cleaning this week and I don't know what to do about the salt.

If the salt hasn't fixed it after a couple of weeks it probably isn't going to, and you might need something else. However, it should have fixed it and if it goes away for a day and then comes back, there might be something in the tank that is stopping the wounds from healing properly or the fish has another underlying problem that is weakening it.

How long has the tank been set up for?
Have you cleaned the filter recently?
Do you gravel clean the substrate when you do water changes?
Did you do water changes every day for a week during the first week of treatment or just once a week?
How often are you feeding the fish and what do you feed it?

If you only feed once or twice a day, you could try feeding them more (3-5 times per day) for a couple of weeks to try and build the fish up physically. Use dry, frozen (but defrosted) and live foods.
Do more water changes and gravel cleaning if feeding more often to keep the tank clean.

A part of a fish's natural defence against parasites and other organisms is to produce lots more slime than usual in order to flush these away. Chemicals and pollutants can also cause this and some medications are specifically designed to promote this effect.
I'm not sure from the pictures whether that's what is going on here, but do bear in mind that often what we think is a bacterial infection or fungus is actually just slime and adding any chemicals are only likely to encourage more slime production! In such cases you need to check water quality and fix any issues and allow the fish's metabolism to return to normal.
A few years ago I bought a group of six loaches which are very prone to parasites and bacterial infections. The change of environment seemed to cause a reaction and they became covered in white patches and spots. However, as they were acting normally and eating I decided what I was seeing was probably just slime. I therefore did nothing and after a few days everything cleared up by itself. Four years later I still have all of them but I doubt I would have had I started bombarding the tank with 'cures'!
PS I'm sure I heard somewhere that angels are particularly prone to excessive slime production.

How long has the tank been set up for? > 20+ years (obviously not with the same substrate, fish, etc) this particular setup is about 3 years old. this veil-tail angel is the last fish added about 1 year ago.
Have you cleaned the filter recently? > canister filer cleaned 3 weeks ago
Do you gravel clean the substrate when you do water changes? > I only gravel clean when I clean the tank not when I only do water changes.
Did you do water changes every day for a week during the first week of treatment or just once a week? > no, I just did a water change at the beginning, then another a week later.
How often are you feeding the fish and what do you feed it? > I feed twice a day, flakes/bug bites in the AM, frozen brine shrimp or mysis shrimp or blood worms in the PM (I alternate the frozen(defrosted) food)

I would gravel clean the substrate any time you do a water change. The gunk that builds up in the substrate can harbour all sorts of nasty things that can affect the fish.

If you have live plants in the tank, just gravel clean around them, leaving an inch or so of dirty gravel next the to the plant. But clean the rest of the tank.

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Try doing a 75% water change and gravel cleaning the substrate for a week, and use salt at the same time. If it doesn't fix the problem, then there is another underlying issue.

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You could add some raw or cooked prawn/ shrimp to their diet. If you have shrimp or any type of crustacean in the tank, use cooked prawn so you don't introduce any diseases.

Get a frozen prawn and defrost it. Remove the head, shell and gut (thin black tube in body) and throw these bits away. Use a pair of scissors to cut the remaining prawn tail into little bits and offer a couple of pieces at a time. Let the fish eat as much as they want and then remove uneaten food.

If you can't find raw or cooked prawns, look for Marine Mix at the pet shop. It is normally made from prawn, fish and squid and blended up into little bits, then frozen in sheets or cubes. You can use this instead of prawn.