quick Question about grow room set up HELP

i am having a problem with my set up i have the intake from outsite at the top of the "cold room" and the exhaust on the wall firing into my "2nd" room.

now the issue i am having is i am getting light out my intake during the night time. i have a manifold blocking off all the light. then a hole cut in the wood to fit in my aluminum sheet metal adapter which goes to 4" then i have on the white flex 4". setup like a 90. i taped a black garbage bag around the white 4" flex not know if thats where the light was escaping but no luck. i wonder if i put on a aluminum sheet metal 90 the a straight run down for a ft or 2. then hopefully that would stop light from escaping. or would it just reflect because of the aluminum. thanks for reading any input appreciated.

Try spray-bombing the inside of your flexi with FLAT BLACK spray paint to reduce light leaks.

good thinking sticky i will try that out thanks. i have a follow up question now though, i found a small black bug in the soil smaller than fruit fly. should i have some type of screen on my intake so that bugs cant enter from there?

flat black spraypaint like stinky said and if that doesnt help, get afew 90deg connectors and make a good light trap, and always paint flat black

its a good idea to have a window screen over the intakes to help prevent bigger bugs from entering your closed environment

get some good sticky traps for precautionary measure

ya sticky traps are a definate or double sided tape... i had/have a bad fungus gnat problem but with sticky traps and a bowl of water and dishsoap mix it kills them before they can do any harm.. you may have fungus gnats as well try the dishsoap thing until you have time to get sticky traps it works really well i left it over night and found about 15 of them drowned and swelled up... i dont know what it is but something about dishsoap they cant resist i think they feed until they die or something

the flat black spray on the flexi hose didnt work. so do you think if i get 2 ducting 90's and a striaght piece that should stop the lgith from coming in without stopping air flow too much
also should i spray paint the inside flat black also on the ducting 90's?

i got the light leak problem fix with with 90 on my flat black spray hose. thanks for the tips. i got another question though. is there any ideas or ways to dampen the buzzing sound of the ballast. i have it sitting 2 feet off my floor on wooden orange crates. anyone have any ideas for me so i can sleep better at night?

Stick it on a speaker stand, to decouple it ( acoustically) from the floor joists.

Ya might try just getting it off of the big soundbox ( orange crate).

If it's older, try unplugging it for several hours ( to allow cap charge to disappate) and tightening up the transformer plates- they'll loosen over a few years.

Also worth checking to see if you're hearing overvoltage @ the trans due to insufficent bulb resistance- ie, cheap or old bulb. Will accentuate 60hz.