Red blotches on yellow tang

[guitareefs]

I have a 300 gallon fish only (for now)

One of my yellow tangs has developed red blotches on its top fin and near his back fin. Not the best picture but the pic shows some red near the back fin

It's been this way for a couple weeks. He's eating very well still to this day. No other fish seem to have it

What does he have and whats the best remedy? Its very difficult to catch him.
And he's pretty dark yellow. Not sure why the pic makes him look so pale

Params are
pH 8
Ammonia 0
Nitrite 0
Nitrate 20
Phosphate.08
Alk 8

 

[Gweeds1980]

Likely to be a bacterial infection... any injuries / fighting etc? If he's fit and healthy, may well be able to overcome it, if it deteriorates, QT and antibiotics is the way forward.

 

[guitareefs]

What about feeding medicated food in the DT

 

[Gweeds1980]

What about feeding medicated food in the DT

You can... use seachem focus to bind it. I hesitate to recommend it as you can't be sure of dosage or stop other fish from eating it too... won't do them any harm, but in the general use of antibiotics, we need to be responsible.

 

[guitareefs]

Thanks for your help!

 

[Gweeds1980]

Thanks for your help!

No worries, try feeding lots of nori and soaking any dry food in selcon or similar. Should help him combat the infection.