Hey Lee,
Thanks again for the response.
Diet wise - I do not feed, nor have I ever fed specific vitamins etc. My fish get a varied diet of frozen food, including:
squid, mysis, mussel, spirulina brine & omega brine, marine cusine, and red plankton. I also feed a sheet of nori daily, and a good quality marine flake food. The clown is still eating well, as ever - he is just finding it a little difficult to actually grab the food, as I imagine his focus is a bit out, only have one good eye to see with. But he is eating perfectly ok.
I have had this guy for 5 or so years, he's always been as tough as nails, and I have never had a problem with him. His other tank mates include a chocolate (mimic) tang, and a regal (hippo) tang - two fish that my experience has shown are good inidcators when anything is wrong with the system - the clown being by far the most hardy fish in the tank.
My task now today is getting a 2.5" flame angel out of a complex reef structure - I want this guy out either way, and I'd like to at least give the clown a day or two benifit of the doubt where he is. Late last night, the clown and the flame were going at at like every 10 minutes - so I turned off the lights to send them to sleep.
On your advice, I wil be setting up te hositpal tank (my q-tine tank is 4*1*1 - so its areasonable size), ready for the clown should things go wrong, and I'll be tracking down the treatment you suggest today, just to be sure.
Thanks again for your help.
Regards,
Matt