Just when I think everything is perfect - the fish are all healthy, the water quality is perfect, and the tanks have become easily maintained, I spot a problem.
This is one of my largest blue marble angels. It is easy to see from this angle that one eye is enlarged and bulging. This is known as Popeye. There are a couple of things that can cause it: injury to the eye or unclean conditions. Since the conditions have been ideal, it's more likely that the eye was injured. It is a peaceful tank, so it might have occurred if the fish swam into one of the decorations. In a less peaceful tank, I might have considered that he injured it while fighting.
So... what to do?
Step 1: Assess Everyone Else
The first step is to determine whether this problem is with one fish or several. If it was occurring with several, I would perform a 50% water change and add medicines to the entire tank.
Step 2: Isolate the Ill Fish
I determined very quickly that the problem is occurring with just this one fish. Its mate, by the way, had not left his side. He was not eating and was hanging out in one corner of the tank, and there like a good friend was his mate, side-by-side with him.
Though I didn't want to stress him or his mate any further, I decided I had to isolate him in order to provide him with the best treatment. Fortunately, the baby angels left last Friday for the local pet shop. I had just moved Lindsay Buckingfish and Stevie Fishnick back to the infant tank, which they prefer because it is higher than the honeymoon suite. So I now had the honeymoon suite empty and available.
I performed a water change to make certain the conditions were ideal, and then I moved the ill angel into that 20-gallon tank.
By moving him into a smaller tank, I remove the possibility that he will infect others, and I also am able to administer smaller doses of medicine.
Step 3: Water Medicines
After I moved the angel, I added medicine to the water.
The medicine I selected is Binox, shown here. Binox is great for any bacterial infection. Popeye will often lead to secondary infections, so this will reduce that possibility. The directions call for removing any charcoal filters and adding 1 teaspoon per 25 gallons. It turns the water somewhat yellow but that also tells me that the medicine is still circulating in the tank.
Step 4: Feed Medicine
Shown in the same photograph is an Anti-Bacterial medicine that is administered as food. This is another reason why isolating the fish is a good idea. Though healthy fish will not be harmed if they ate this food, it could cause any bacteria to be resistant to the medicine as they build up a tolerance to it. Therefore, it is best used only when necessary.
The angelfish is currently not eating. Fish can go for days without food so at this point, I am not concerned. I will continue to feed it small amounts at least twice a day. As he begins to eat again, I will feed it more until I know he is well on his way to getting back to normal.
Step 5: Patience
All I can do at this point is monitor the situation. If he shows no sign of improvement in four days, I can perform a 25% water change and add more Binox to the tank. Within four days, his eye should have become reduced in size.
How long he remains in the tank will depend entirely on his condition. As long as he shows symptoms, I will keep him isolated. When he is back to normal, eating again and his eye is back to its normal size, I prefer to move him back to the community tank where his mate is.
Stay tuned and let's all hope this beautiful ten-inch blue marble responds well to the medicine!