Hey everyone..
I noticed a musty smell in my grow tent a few days ago and have been trying to figure out where it could be coming from. I’ve thoroughly inspected all plants in the tent (5 G13 strains) and all appear to be healthy (with the exception of a few lower yellowing leaves) with no signs of mold or powdery mildew. Humidity in the tent accidentally got up to around 70% the day I noticed the smell and now is back down to ~55%. Temp stays between 73-76F. They are 6 weeks into flowering. I normally water once every 4 days but did water twice in 3 days this week to give the plants a little extra nutes because of the yellowing.
I took out the pot saucers earlier today and cleaned them out. They had a small about of stagnant water sitting in them. The buds smell fine so my best guess is that the musty smell is coming from the soil.
So musty smell could be from over-watering and an early sign of root rot; or less likely some water might have got under the floor pan of your tent and maybe molding up, those are the only things I could think of that might cause that kind of an odor?? Hope you find the cause, they look very healthy though, maybe letting them dry out well before the next watering might help good luck!