White Patch on Tropical fish /Clown Loach sustain please?

I bought four clown loach on saturday and notices 2 days ago on one loach there is a strange white patch on its body below its fin. Its not white spot/Ich as not just within little patches and its not that cotton wool fungus thigy because it doset have any texture like that. I looks as though the slime coating have been damaged or there is some sort of fungul infection. No other fish give the impression of being to be affected and the clown loach in question is acting without fault normal.

So...whats wrong with my fish??

Sounds like a bacterial infection.

Go to PetSmart and get your dampen tested to see if there is something wrong with your river. You can buy Melafix, Pimafix, Quick Cure to treat the fish in your tank.

Probably a bacterial infection/parasite. Check your water, and carry parasite killer from the pet store, this is highly recommended. You should raise your heat a bit, and be putting one teaspoon of salt per five gallons of water to make certain they die off faster. Good luck!
Answers:    Clown Loaches are scaleless fish, so you never use salt which would burn them and whether you do use any medication it has to be at half the recommended dosage.

They are prone to white spot/Ich, but you can see the fish and we can't. If you think it's a short time ago a scrape, then it could be just a chafe and will heal itself.

I would raise the temp, but be reluctant to rush to the medicine cabinet until that time I was sure what was wrong. You could use a thoroughly weak dose of methylene blue as a preventative measure if you hold it to hand or watch the fish and see how things develop. If it's eating and playing beside the others it could just be damage to the slime coat, they do try to fit themselves into holes that are smaller than their bodies.
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