So I woke up this morning to find that my boy Harlequin has a nice fluffy whitish pom pom just behind his dorsal fin. A slightly panicked google shows that it might be cotton wool disease. And I really didn't need to find that it's another name for Columnaris. That's one scary disease.
I just found that Seachem has a listing that looks like what he has simply called "fungus" and says that it happens when the fish is already sick. He's been acting normal with good appetite, although he didn't want breakfast this morning.
I have Kanaplex and API Furan 2 on hand. I'm not sure if I should try to get some SulfaPlex, that I will probably have to order from Amazon since fish stores here don't carry much medication.
I can't find any information but wonder if I should treat him with the KanoPlex, which is an antibiotic that says it also treats fungus, in case he does have something systemic that he's not showing symptoms of.
What I haven't been able to find is if I need to remove the plants and driftwood before treatment. Since they can carry the bacteria should I just trash them and start over when (hopefully) Harlequin is well?
He is in a long established Fluval Spec V tank. I clean his tank every week with about a 25% water change with Prime added, siphon the gravel and wash the filter and medium. There is no charcoal in the filter, just biomax pellets in the sponge filter. No changes have been made to the tank, nothing was added. His only roomies are a couple of nerites.
His tank was cleaned on Sunday. Parameters were Ammonia 0, Nitrites 0, Nitrates 5, pH 6.8.
Here are a couple of photos of Harlequin and his pom pom: https://imgur.com/a/mpeksRg