Seed recommendations for a beginner grower?

ahoneybadger said:

400 watt HPS and MH bulb in a 2 foot long by 1.5 foot wide area. roughly 4-5 feet tall so total about 15-20 CU ft.

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Jogro said:

That's a bit of overkill.

Rule of thumb is that without CO2 enrichment, optimal lighting is about 70-80W of HPS per square foot.

With a 5 x 2 x 1.5 foot space you're going to have only 3 square feet of canopy to illuminate. So you could get away with a 250W HPS or perhaps even less.

Running more light won't really hurt the plants, but it sounds to me like you are growing in a cabinet or other enclosed space. If you are, unless you have excellent ventilation, you're likely to overheat that space with 400 watts of power draw.

In terms of yield, its usually expressed in terms of yield per square foot (or meter) of canopy.

In that space, figure you could cram in 2 (or at most 3) medium sized plants. I think you'd be doing extremely well if you could pull out 6-8 ounces of trimmed dried bud from that space.

A really accomplished grower, who is experienced with the strain and optimized the space for yield using hydro, good training, etc, might be able to pull out a bit more, but you couldn't nearly expect to your first time out.

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ahoneybadger said:

I plan to have a 200 CFM fan in there (Is that overkill for that small space? noise wont be an issue). Would that keep temps down and also will that be pulling too much air?

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Jogro said:

So you're running 200cfm though only 15 cubic feet of space? Yikes.

Assuming complete dispersal, you'll be getting a complete air exchange 13x per minute or roughly every five seconds. Don't forget your pots and other doodads inside will displace some volume, so the free air volume in the box will be less. On the other hand, its hard to realize the full rated efficiency of a fan because of turbulence, air resistance, etc.

But yeah. . .I'd think that will be more than adequate ventilation to keep temps down inside the box to just barely above that of the temp of the air you're bringing in. If your space is set up already you can simply trying running it for an hour or two with no plants inside to see how hot it gets, and I'd strongly suggest doing that before putting any plants inside.

In terms of too much air, no, you can't really "overventilate" plants, but if you're moving too much air there may be turbulent flow and the plants may start to wave around as if in a stiff breeze! (A little "wiggle" is actually good for them, since it "exercises" the stems and makes them tougher").

Don't forget to stick a filter on your air intake holes, or with that much flow, you're liable to suck in things (eg insects) that you may not want in there!

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