Puffer-cloudy eyes

Question
Hello, THank you for taking my question!
We have a smaller (about 2") porcupine puffer in our 180 gallon saltwater tank.  We got him about 2 weeks ago.  He seemed okay until yesterday.  His eyes are very cloudy, and now starting to look a bit "stringy" like bits are hanging from the outside.  He won't swim around, and he's bumping into everything.  He puffs up often now because I think he can't see and gets nervous.  We've removed him from the big tank and into a smaller one by himself.  What do we do to get him healthy again..or can we?

Answer
Hi Victoria. Eye problems are very common with these kinds of puffers. Usually it starts when water quality starts to decline. These puffers are not very tolerant of ammonia, nitrite, or nitrate in their water and require excellent water conditions. Sometimes by simply correcting the water quality these types of infections will clear up on their own. However it seems like it has gotten too far to treat that way, you may need to start him on a course of antibiotics. Adding antibiotics to the water will destroy your good bacteria and water quality should be tested on a daily basis to ensure the ammonia and nitrite are not reaching toxic levels. If you already have him separated into a hospital tank this may be the way to go. If the puffer is still eating then you may want to try soaking the food in the antibiotics at the rate of 250 mg per ounce of food. Feed this two times daily for two weeks. It is important to do this for two weeks and not stop treating even if he looks better. The antibiotic I recommend is kanamycin. It treats both gram positive and gram negative bacteria also known as a broad spectrum antibiotic. The problem with this infection is that if let to get too bad it will lead to blindness. If the fish can't see then it can't eat and will usually die of starvation even after the infection is gone.