This is my parents tank, 90g FOWLR. Their rocks seem to been getting this grey powdery stuff on them, they said when they move them it all falls off. They shut off their lights for 48 hours, it went away on half the tank that doesn't get any sunlight, the other half still has it. Is it a bacteria? Thoughts?
thanks!
https://onedrive.live.com/redir?res...authkey=!AAqezVTsO83B_io&v=3&ithint=photo,JPG
thanks!
https://onedrive.live.com/redir?res...authkey=!AAqezVTsO83B_io&v=3&ithint=photo,JPG
