Hi, I have zebra blenny in my reef tank and I've had him for almost a year. Just today, I noticed on only one side of him, he has a fungus or parasite that looks like fur or feathers or something. It is white. It just appeared today so he is not acting any differently. Is there anything I can do? I have invertabrates in my tank so I don't want to harm them with any medication. Please help. Thanks a lot.