"mould" On Lemon Tetra.

I have had 6 lemon tetras and 4 rummy nose tetras in a 58 litre tank since a week on saturday. I fishless cycled the tank before I started and ammonia and nitrite have remained 0 since I started the tank, although the nitrates also remained 0. I was a little suspicious about this but atrributed it to my new plants I got so the fish could hide. I did my first water change on saturday, everyone seemed a little stressed but all went back to normal.

Tonight I noticed that my smallest lemon tetra has a white/grey mould type patch on 1 of its sides just below its top fin. This isn't fluffy at all yet, it sort of resembles the mould that you get on cheese without the green. There is no sign of any significant wound, although possibly a small pink scratch to one side of it. The mould seems well stuck onto the fish and is not at all fluffy The fish and everyone else in the tank is eating and acting normally.

Current water stats are ammonia 0 nitrites 0, nitrates pH 8 (stable).

What should I do? I have aquarium salt, melafix, interpret anti bacterial 9 and protozin for whitespot (not it i know) from previous sick fish, and i can get to my well stocked lfs tomorrow. For tonight I am preposing to turn down the heat as it most sounds like fungus/columaris and add a dose of melafix.....

Help much appreciated!

Edit: I don't have a hospital tank but I could possibly fashion something lidless with a crate and I have a second filter running in the tank (came with tank but proved to be small and useless but left in with proper fluval 2 as couldnt see the harm) but no spare heater.....

Greyish white patches can be columnaris and with the pink mark it sounds more bacterial.
If there no signs of flicking and rubbing I would treat the patch as columnaris.

Thank you for such a speedy reply!

I have turned down the temp, dosed with melafix. Tomorrow I am going to:

1. Get hold of some Maracyn medicine

2. Get hold of some Terramycin medicine (can i be dosing with both?)

3. Add some salt?

4. Get hold of anti bacterial fish food.

Should I water change every day or will this just increase stress?

For columnaris in the united states maracyn one and two.
Make sure there not flicking and rubbing as greyish white film on fish can also be parasites.
I woudln't bother with the salt just yet see how things go.

I'm in the uk, so the fish shop said that they cna't sell maracyn as it is an antibiotic...

So I have king british fin rot and fungus control, the best I could do.....

Sorry when you said maracyn thought you was in the united states.
In the uk for columnaris myxazin by waterlife and pimafix.
You could try the king british med while you could get the other meds.

OK will do.

I just have a quick question on the meds. I want to do water changes every day or every other day - what should i do about redosing the tank? The instructions give the dose per litres but aren't very descriptive on when how often to re add the medicine or what to do about whater changes.

Never used that med so don't know the dosing instructions, it should tell you on the bottle it's self, or instruction booklet or on the box.
Is it a once dose treatment for seven days.
When you have to preform a water change during a med course you just add the correct amount of med back to the water removed.

So I used the king british med until I got hold of the other ones. The fish is still swimming about and eating and nobody else looks ill.

The white patch doesn't look to have got any bigger, it still isn't really fluffy and cotton wool like but it has gone very red down one edge.

Obviously still got a few more days of the new med to go but am a bit concerned that I need to be treating for something else as well....

I managed to get some pictures (sorry not great....)

OK during today the white looks fluffy.

Is there anything else I should do?

Salt?

Is it easy to get a hold of medicated food or could I soak the food somehow?

Its still bacterial columnaris can be pink it comes in different colours.
I would change your med it's not doing anything.
I would get some anti internal bacteria med by interpet and pimafix.

Unfortunately I had already transferred onto the pimafix and the myzaxin but it seems it didn't work as unfortunately I found him dead this morning. At least he was still swimming around and eating last night so I don't think that he suffered too much.

Luckily this doenst seem to have infected any of the others, but I take it that I should keep up the meds just in case? I read columnaris is very contagious, maybe they are just doing enough to stop it spreading. Or a big water change? Slightly concerned that the meds messedup my cycle as have a slight ammonia spike

Arg all the others seem very stressed but no sign of white bits and water stats are perfect. Doing a 50% water change just in case of I don't know. If anyone has any advice all v appreciated....

R.I.P.
Have you increased aeration in the tank while using meds.