Strong weed smell at night

Yep, the strongest smells I get are first thing in the morning before the lights come on. I run a filter all night long but still, when I leave the house in the mornings I can smell it. After an hour or so of the lights being on, the smell goes away.

Also, light kills terpenes, which is why it smells less when the lights are on.

I read this thread yesterday and my girlfriend mentioned the plants smelled a lot lastnight so with this thread in mind I went to check and the lights had gone off 10 minutes ago.