Too much negative pressure in tent?

So, i had negative pressure with just the intake fans and exhaust fans.
The past day i’ve been testing what temps would hit with lights on, so i have an idea before i start growing to be more prepared. I was hitting 95F which is WAY too high, so i stuck a portable AC in there and the temps are at a nice 78 now.
But now i have way more negative pressure because of it to the point there is now way the sides of the tent can be sucked in and further.
Will this negative pressure be a problem? Is it a bad thing for it to be this intense?
Any information is much appreciated, thank you.

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The only bad part is it does consume some grow space. If your plants aren’t near the edge you’ll be good


I turned the lights back on, and my temps are at a steady 84F, is this too high?
I read that below 85 is fgod, but ive also read that i have to get below 80.


Mine run at 84 all day, year round.

awesome, thank you for the help as always!

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Can you partially block your discharge? That should up the pressure and drop the flow. A centrifugal fan will cope much better than an axial fan. Also, can you solely use the A/C as your inlet? That might solve the pressure drop issue from the other end… I had very similar heat issues using an HID in veg - reverted back to fluro and it sits perfect 22C/ 55%RH

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If you don’t already have a variable speed on your exhaust fan, you might consider can dial it up to increase negative pressure or dial it down For Less.

I had the same issue with an hid, switched to an led and temperature dropped 10 degrees and humidity went up 10 points.

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To drop negative pressure open a vent on bottom. Most tents have a few.
The reason there is negative so much is because intake cant keep up with exhaust.