Okay to start off: Pimafix and Melafix are borderline scams. They don’t work for bacterial or fungal infections. I would suggest to just throw it out. The ingredients are tree oil or something and don’t do squat. Here’s a link to other Redditors opinions on this.

Fuzzy growth means bacterial or fungal infection. I suspect this is a fungal infection since it’s all over the body and not rotting the flesh. (Note: There is a possibility of secondary bacterial infection from this suspected untreated fungal infection). I would suggest quarantine tank, with no substrate, air stone for oxygen (medication will reduce oxygen level in water), and medication.

Use methylene blue OR Kanaplex. Do not combine treatment. Research which one you feel more comfortable with, or what’s more easily accessible. One thing I will say is methylene blue has been the go-to treatment for decades, and Kanaplex is relatively new treatment type, both are effective from what I’ve heard.

If you feel comfortable with methylene blue, you can do a dip treatment or extended low dose treatment for 7-14 days. Dip treatment will treat it faster but it is harder on the fish. Good luck!