sorry mate... just a photo with no additional info isn't going to get a lot of help. what are your water parameters? did you temperature match? did you condition your water before adding? is there a difference between your pH in the tank & out of your tap?
Phone froze as I was trying to add info than I tried deleting and it wouldn’t work. I did a water change yesterday. Just came home from work. Fish looked lethargic and it looks like this guppy has some stuff growing on it. Not sure if maybe too much bacteria supplement or just the end for him.
ah ok sweet. are you cycling? have you tested ammonia & nitrite?
Did you condition the water before adding it to the tank?
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