HELP everything is dying wtf

[MilitantPotato]

Growth on mouths and grey scales sounds like columnaris. You'll likely lose the entire stock, and any other tanks that come in contact with the equipment/your hands if they've not been disinfected. Check this page, I've had about a 30% survival rate using the meds they suggest, when caught very early. http://www.americanaquariumproducts.com/columnaris.html