Building your own grow is easy but you need to know what your doing, here are a few guidelines to building a setup.
One of the first things you need to think about before setting out and collecting parts is how much bud do you need, and how often? Will you to be growing for personal use or to sell, or both? Or are you just growing as an experiment and don’t plan on being self-sufficient?
most plants finish around 8 weeks and veg can be anywhere from 2 weeks to over a month, but you can make up by having a seperate veg box and veg the plants right up to when there ready to flower then bring them into the flower box and put them on 12/12. Or you can have 2-4 plants per foot SOG style and veg for only 2 weeks. Yeild will have to be guessed by strain and grow style. Soil can yeild around .5 g/w max and bubbler can get around .7-.9 g/w U scrog and stadium is around .1-.3 more then flat. But don't expect to max out your yeild on your first grow. You will have to learn the strain and optimize the setup and ferts.
Now you have to find our limit on how big you can go. Some may only be able to have a small cabinet stealth ScrOG grow usually in the 70-250w ranges. And some can use a whole closet and have 400 or 600w light. While others can devote a whole room to commercial growing and have an array of 600+w lights with many plants. If you’re growing in a house around 3000 watts and your power bill might send up a red flag and get busted. If you’re growing in an apartment 250-600w is a good arena to stay in. You have to ask yourself what’s realistic.
The first thing you need to do is get power into the box, most people use a power strip like below, they are good enough for most grows up to around 250w
<-6 outlet power strip-> any more then 250w then you should run solid copper wires and have GFI outlets and have the grow have its own breaker.
Ventilation is one of the most important factors to a grow space. If you don’t have enough ventilation and the box gets hot and the co2 gets used up. You can dramatically loose yield from inadequate cooling and fresh air. You WILL need a fan in any grow box.
Fan placement is key; heat rises so you want the exhaust fan blowing out the top of the box and the inlet holes at the bottom. You don’t need an intake and exhaust fan because if you just have an exhaust fan blowing out you create negative pressure and this will suck from the inlet and any gaps you have. This is great because the smell is contained as long as you have a carbon filter after the exhaust fan. The inlet holes should be at least the size on the fans, optimally around 2x the size. The bigger and smother the air inlets the quieter the air movement will be, so radius the inlet edges. A PVC elbow works great as a light trap, just paint the inside black so light doesn’t bounce though it and emit a glow out the end.
You want to evenly distribute the air across the grow box for even growth. A circulation fan in the box blowing across the buds is a good idea. It also cools the buds and increases growth and yield.
Some of the easiest fans to use are computer fans because they are quiet and reliable and cheap at around $4-$15. Opt for the ball bearing fans because they last longer, are quieter, and don’t go bad and get extremely loud like bushing fans. One 80mm fan is good enough to cool a 70w HPS, or floros around the same wattage. 2-3 fans would work well for a 150-250w HPS. To power the fans which run on 12v dc use an AC/DC adapter that you can either buy one,
9v DC adapters 12v DC adapters
Or just look around your house, they come with many small rechargeable electronic appliances, I know I have collected around 7 that have just been laying around. If your doing a stealth setup you want a 9V charger so the fans will run slower and quieter, or you can buy a 12v and use a dimmer.
The adapters rating is in milli amps and the fans rating is in amps, so to convert move the decimal over 3x, so 600ma=.6a . You want to keep the power supply rating higher then the fan draw, otherwise your run the risk of overheating the charger and it failing on you, or making a fire.
If your using a carbon filter with a 150w+ watts you may want to buy a centrifugal blower like a Dayton.
<-Dayton blowers->
They push the air with more pressure so are much better for pushing through filters, look on ebay for a used one that will fit your application. The Dayton’s are a bit noisy but you can muffle and dampen the noise by hooking it up to a light dimmer and have the fan on some kind of dampening material. Always put the carbon filter after the fan with centrifugal fans. Listen to the fans inlet when it's on and if the airflow surges (sounds like a quiet helicopter) instead of the sound being constant, the outlet of the fan it too restricted. That can either mean the carbon filter is too restricted or the pipes are too small.
Placement of the fans is key for noise. If you place a fan the center of a wall or ceiling the fan will shake the panel and make your grow box into a big drum increasing the noise. Place the fans in corners where the structure is stronger and less likely to vibrate.
Grow box sizing should stay in the 45-70 w/ft with soil and but you can grow with 75-90 w/ft if you need or want. But unless if you hydro with co2 enrichment or allot of airflow the plants wont be able to use all the light you give them efficiently because they are limited by the amount of nutrients and co2 the plants can absorb. If your growing a stadium style setup or U-ScrOG you can have higher w/ft because the effective w/ft is lower because of the increase in canopy area and absorbs more of the light.
To calculate how many w/ft in a given space use this equation
watts/ (depth x width)
Now that you have an idea on the dimensions, lights, and fans you need to find or make a box. The minimum height is around 28” inside height for growing small 70w ScrOG, you can grow shorter by having a lower screen and less soil but the lower screen increases the chances of snapping a branch and less soil can lead to root bound or medium that dries out too fast.
If you plan on growing more then one harvest your far better off having a veg box for a moms and cloning. The benefits of cloning are you know the plants a female and you can flower anytime because it’s a mature plant. So either integrate a small veg box with either a small 30-50w MH, some daylight CFL’s or 1-2’ floro tubes in a mix of warm, cool and or daylight floro tubes. With veg you only need around 25-40 w/ft of MH, cool, or daylight to keep the plants short. And the veg box only needs to be around1’ high min and as narrow as 6-8”. The warm bulbs will help growth but without the blue spectrum the plants will stretch.
U-ScrOG grow Stadium grow
(stadium can be done with soil or bubbler also, you just need to make stadium shelf for each row of buckets or pots to sit on)
Good 70 w setup An awesome potential 250W cab with bottom shelf for electrical, fert storage and hydro pumps if growing hydro A good 70w cab A good 150w cab
-Gr0wer