Hello Abbothayes88,

Welcome to the boards. I couldn't enlarge your pics much, but from what I can see, it surely is a mould, especialy if a dehumidifier is helping with the situation. Heater at night is a good idea to help dry air, but you can still use the dehumidifier at night if you don't need the heat. Humidity levels increase during the dark time due to the plants transpiration.

Mould is a air born pathogen carried by spores. Since you've had mould in your grow area spores will likely be there. You need to clean your grow area with a mild bleach or hydrogenperoxide solution....all surfaces; walls, cieling, around your lights and fixtures, every nook and cranny.

Good luck with it and good growing.
OM
oldmac Reviewed by oldmac on . Can anyone identify the problem? plants are 3 weeks into flowering but dont smell and i have noticed some leaves near the bottom have some kind of white fluffy stuff on them which is killing some of the leaves, ive pulled this off the plants and ive included a picture not too sure what this is but im pretty sure its to do with a drop in temperature at night also was a bit wet in the growroom but ive added a dehumidifier and that seems to have sorted that. This must be some kind of mould but i just need to know what mould it is Rating: 5