It appears your fish have ich. It's a parasite that attaches to fish during one of the many reproduction stages it goes through. If you don't treat your fish quickly they are going to die.
You can tackle this problem several ways and I will be brief:
You can med your reef with reef safe ich meds or non reef meds. If you have inverts or corals you will need reef safe meds.
I recommend no-ich med by Vet Med; make sure it's the reef safe as there are many versions out there.
You can treat in the tank directly with this stuff and it will not affect your corals or inverts.
If you have a hospital tank set up you can treat the fish with meds that are a little stronger and more effective; they usually have a copper base to them, that the parasites cannot tolerate.
If you opt to stick with treating in your tank, that's okay, purchase the med and dose it according to instructions do not deviate.
You can raise the temp slightly to 83 or 84 degrees while you introduce this med to the tank, as it will speed up the metabolism of the reproducing parasite, this means more parasites will come in contact to your med.
This is important as the parasite is only susceptible to this med during a floating stage of the parasite.
After using the med, you should see within two days a change in the fish. If they come around and begin accepting food, you need to fatten them up with pellets that have been dipped in garlic elixir.
This promotes the appetite of the ailing fish it will also give them vitamins that they can use to build up the immune system.
You can also not run the lights during the first couple of days of treatment as the lights allow the parasite to find the fish more easy during the attacks.
Now, if you are going to treat them outside of your tank, there is hyposalinity that will help out, this is another method that most reefers do and is very effective but takes time and patience and more importantly a hospital tank.
I won't go there unless you are going that route.
Let me know what you decide to do?
MG
