What's this smell?

[GrowrLvlNoob]

Ok so I have a musty smell coming off my plant, it's way worse at night. Air flow is great 2x 18 fan 2* 4" inline and one 6" inline. The large fans only run day cycle, the rest 24/7. The RH never has been above 40% ever. Soil grow, 5gal ffof, go box nutrients, 600w led. No signs of mold no over watering.... I'm thinking it's just the way it smells but would love some input from the community.

 

[GrowrLvlNoob]

Do buds "burp" at night? Been reading different things I really don't think it's mold

 

[Lazarus13]

I have had strains that smelled moldy/mildewy at points in the flower stage. I thought i had sprung a leak and moved my whole set up to check the carpet underneath. After a week or two the smell went away and turned to a more diesel fuel smell.

 

[GrowrLvlNoob]

Awesome thanks i figured it's something to do with chemicals released during transpiration at night