Unable to determine what type of fungus this is (pics attached)

Hey, guys. New to the forum. Unfortunately, I'm posting here because I'm not sure what I'm dealing with. My RedDwarf Gourami has a web-like fungus growing on it and I'm currently treating with Maracyn 1 and 2, he's more active but it doesn't seem to be going away. Today will be day 3 of 5 of treatment.

Some background on my tank, it's a 30gal, all parameters are perfect, I've done frequent water changes. He had tank mates, a few Zebra Danios, that had passed on due to this fungus. The Maracyn wasn't working for them, I guess.

I've attached a few pictures. I was only able to get one side of him, but the other looks just like it. Hopefully I can get rid of this thing ... :mad2:

Thanks in advance!

Just did a water test now so I can post proper parameters, realize this is important:

ammonia: 0, nitrate: 20, nitrite: 0, ph: between 6-6.5 (similar shades, more towards the 6.5) .. also should note that I have a pretty decent sized airstone in there constantly running.

Thanks, again.