I have a grow cabinet that is 3X3X6 and I have a 400HPS that give me very nice buds. I can also flower about 6-7 plants at a time depending on strain. Ventilation is an absolute key when you mix that size cabinet with a 400 HPS. I would highly reccomend a cool tube or something similar.

I have a 424 CFM inline Vortex hooked up to a DIY filter and it is probably overkill. I bought it with intentions of getting an air cooled reflector in the future. It's a big ass fan but it certainly does the trick as far as my ventilation is concerned. I use passive air intakes and that puppy moves so much air, the leaves on my plants ruffle in it's wake.

Good luck with your scrog. I plan on doing one sometime but right now I am just learning to grow some very good meds. Once I get my medicine cabinet restocked, I will give a scrog a go.

I am planning on getting an air cooled reflector. That way I can take the heat right out of the source. The hydro shop in town has plenty of 400w digital ballasts and air cooled reflectors. I was also going to use a passive intake system near the bottom of my cabinet and an out-take fan near the light to take out some of that extra heat just in case. Does this sound like enough ventilation?

demonicus: That is next on my list to figure out.

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