Can you take some pictures?
This is from Beth's FAQ...
When posting in the Disease Forum, speed in getting answers to your fish's disease problem is uppermost on your mind. Thus, here are some Disease Forum suggestions:
Probably one of the most frustrating things we can deal with is illness in our fish. In most cases, hobbyists aren't sure what they're up against, let alone how to go about properly treating the problem. When someone posts in this particular forum, it is because they have an emergent need for info and reliable treatment recommendations. Often times, however, the initial post is lacking in vital information that is needed to accurately diagnose a health concern and offer advice.
Example; "I think my fish has ich or something, what should I do?"
It's important to be as specific and detailed as possible with your problem, much as you would with a family doctor when you are ill.
Some things to be included in your original post/question;
1. State the problem as you see it and provide details.
2. List symptoms...white spots, not eating, labored breathing, etc.
3. How long the fish has been exhibiting these symptoms.
4. What is in the tank; other fish, live rock, corals, inverts.
5. State the tank size, and how long the tank has been up and running.
5. Diet; what are you feeding the fish, and do you use any supplements like selcon, zoe, zoecon or garlic.
6. How long have you had the particular fish and have there been any new additions.
7. Was the fish quarantined prior to placing it in your main tank, and do you have a quarantine tank that you can use? EVERYONE SHOULD!!!)
8. Have you tried any treatments thus far before posting here. And, if so, describe what you have done.
9. Water parameters!!! ammonia, nitrite, nitrate, pH, temperature and salinity. These are very important to know. Please don't say "my water quality is good". Give real numbers. It could be the key to solving the problem.
Some of these things may not seem relevant but they are, and many of them can aid the moderators and members knowledgeable in disease to quickly give you advice that will aid in getting your fish back to good health. It's almost a sure bet that these questions will be asked if you don't provide the information, so save time and frustration and be as inclusive as you can in your first post.