Conflicting light schedules

[Glifho]

I did try to do a search on this, but came up empty handed.
Question to ponder, I have 2 tents. 3x3 veg and 4x4 flower. They are within 2 feet of each other. I'm pretty sure most tents are set up the same with the intake screen air vents are along the bottom 3 sides of the tents.
What I'm asking is, if I have veg tent going at 18/6 light schedule, and flower going at 12/12, I have a 6 hour overlap of light coming out of veg tent when flower tent should be dark. Is the light penetrating into flower tent from veg tent a concern? If I cover one tent air intake screen or the other, do I risk
choking off air intake?
Probably over thinking this, but any input would be appreciated.

 

[yarddog]

Yeah, a light leak that large can definitely cause problems. You need to find a way to prevent the light from leaking into the flower tent.

 

[Dalahaze]

That question is a hard one to answer, if in a dark room you open the flower tent and it is any brighter than a full moon they yes you will have to close the two side vents, with that being said as long as your exchanging air enough for the tent not to deplete it CO2 supply your good, but if the CO2 levels drop below 350 ppm the plant slows photosynthesis way down as CO2 is a key component, effectively stopping it from growing until it has enough CO2 to continue.

 

[Hackerman]

I have the same issue and I keep the flower tent closed up tight with an intake and exhaust fan. I use baffles on the intake to stop light from entering.

I did leave a back flap open once and it did mess things up. The plants were in a "half reveg" state before long.

 

[grass hopper]

enter closed tent during dark time to see if any possible light leak. if light leak, put 100 cfm make-up air fan on opposite side, ducted with 2 or 3 - 90 degree metal elbows. paint interior of ducts flat black. goodluck.

 

[Glifho]

Grasshopper- that was kind of what I was thinking with an intake duct. Painting it black or finding a black colored one, I didnt think about. Thank you all for the responses.

 

[Hushpuppy]

That is what I had to do with mine. I actually built a plywood box and mounted 2 duct connectors on either side of the box and then had screened openings around the box. then I used black lined flex hose from the box to the duct ports in the tents. There was enough turns and such to keep light from getting in. Using the storm window screen material on the box helped to keep out dust and debris. I just had to periodically vacuum off the dust buildup.

 

[grass hopper]

i worked with duct for many years and was still very impressed on zero light leak using (2) 90 degree metal elbows with a 12 inch piece of straight pipe in between elbows. forming a S shape or a U shape. the flat black paint will not allow any light beyond. paint, ducts cheap to buy and duct tape connections are fine. self tappers not needed..