HELP PLEASE! how big do my intake/output holes need to be??? 3x3x3 cube well sealed

heres a pic of the inside...



I'm thinking 1 to 1 and a half in pvc intakes in the middle on each side wall close to the bottom...if that makes any sense. two holes, one on each side, about halfway to the back of the box, on the floor-ish. they won't protrude much on either side inside or out, just enough to seal around the outsides, and just enough inside to attach a 90 degree elbow, another short section of same length pvc, and another elbow, this one being a 45 degree...one on each side of the box pointing opposite directions...if you follow.

for the output, I'm thinking a 2 or 3 inch short section drilled right in the middle of the top of the box. my MAIN QUESTION. can the output be a 1 inch or 1 and a half (the same as what i want to use for the intakes) or does it have to match the diameters of both intakes added together? I'm wondering if it can be the same so i don't have to buy two bits. i will also at some point be adding a sort of u bend to the output with activated carbon in the bottom of the u to scrub output air....???

any and all ideas welcome/appreciated!

oh! btw the temp max over the course of its day period was 88 fahrenheit. 38 percent humidity.

*update*

the mid-night cycle is at a low of 58. is this too low? i know its pretty cold, but...idk...could/should i insulate the exterior of the box? humidity went up to above 50 percent...and rising still

I see no pic? Also I'd use at least a 3 inch vent in and out. I would also try to get the high temps lower and the low temps higher.

the pic is in the op. check out the link in my sig to see the full story, but yes i know thats what i need to do. requesting help on how. there would be a 2 inch intake technically, 2 one inch intakes...equals two inches of intake. i was thinking of 2 inches of output to match, and as there is the probability of a carbon filter, was thinking of making the output bigger.

does the placement i mentioned seem decent?

Your pics don't show for some reason, I'm on an iPad so that may have something to do with it, I don't know. My cab uses several 1.5" holes for intakes because it's passive but for an exhaust I say 3 inch because how are you drawing the air out? mine is a 3" hole with a bathroom fan.

so i did 4 holes total. each are 1 and 3/4 inch. one on the right side, one on the left. they are both at floor level. 2 holes in the ceiling, centered. 1 and a quarter pvc pieces go thru each hole, with various 90 degree and 45 degree elbows to direct air flow. the two coming out of the top are like a chimney...

they are all passive so far. my nighttime temps get SUPER low and I've now burned all my plants because there wasn't any ventilation yesterday...

you should still be able to see the pics on ur iPad...i work at an apple store lol. you must be signed in...thats the only other thing i can think of, other than this sites server seems to go down a lot...

*edit*
sorry it was my privacy settings...

Well you need to move that air somehow, you can't have a passive intake And exhaust you know? Although I don't recommend it, I'd probably have your fan on the same timer as the lights because your temps would be too low in lights off. If humidity becomes an issue then you'd want to run the fan 24/7. Check the thread in my sig, u can see how my vents are

Edit: I can see now! It looks like your plants are stretching. I would put a single bulb like an inch from each plant as I don't think the current quad setup is optimal yet. Might also be overwatering causing the stretch.

Like take 2 fixtures out, bring all the cups next to each other and put one plant directly under each bulb. They've already started to fall over, so when you transplant them just sink the plant that much further to get them upright again.

thanks man i definitely appreciate the info...

they stretched cause i didn't have the cab built when i germinated. i used an aquarium with lights that were wayyy too far away. they stretched really fast...then i got the cab going sorta and now just ironing out the issues...

i will be transplanting either tomorrow or friday. definitely sinking those babies in a lil...i should still cluster the cups together under just one fixture? keep in mind this is more to get a functioning cab up and running, this is my first grow, and its just bagseed. not that i don't want them to do well...but i am expecting problems lol.

anyway thanks for the advice, and id like more! lemme know about using just one fixture for now, cause that will help the electric bill lol...thanks again man!

Run your lights at night and have the off cycle during the warmer part of the day

Run the lights 24/7 replant them in bigger pots and put em deep to fix the strech problem with the lights as close as you can get them with out burnning the plants

thanks a bunch guys...

definitely guna transplant them today. planned on sinking them in deep...not *really* worried about the plants tbh kinda trying to get the kinks worked out for the cab. if you check out the grow in my sig, you can see the whole process. i mean i would LOVE the plants to do better...and they are! check out the grow lol.

anyway went with 1.25" pvc (again check the grow!) for intake and outputs. two intakes in the bottom middle sides. lol. and two outputs center ceiling. the two in the ceiling will be supplemented with two more, coupled outside of the cab, adapter to 4", 4" inline fan 165 cfm pushing through a carbon filter.

thanks for the advice tho guys, and PLEASE check out my grow/cab. could use advice on how to help keep the temps more steady, what are acceptable extremes in temp/humidity, etc.

post some update pis you have to keep your thread up bro

is there a way that I can close a thread? i got my question answered, and now this thread is pretty useless...i mean i think right? lol

here!

kind of an evolution of where my cab started to where it (they) are now.

can get more detailed pics or explain anything if anyones interested...