building new room

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fellowsped

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Hello everyone long time member but I haven't been growing for several years. I finally have time, $ and a place to grow again so I'm going to get back at it. The room is going to be 4ft/10ft with 7 ft ceiling. My plan is to run 2 1000w HPS each one positioned over a 4x4 soil bed. I have access to a fresh air via a window and am debating exhausting the air out the roof of the room and then out the side of the building. That will keep that exhaust about 15ft off the ground lessening the chances of it being as noticeable. I plan to have a fan blowing between the light and the tops of the plants to keep heat buildup from happening. Also another fan blowing the air around the base of the plants to keep good air circulation up through bushy plants. The plants will all be clones put into the soil bed in rows. They will be given a couple few weeks to veg then quickly put into flower. Plan is for a Sea Of Green grow.
Now for the questions. First what size exhaust fan would you recommend? Last indoor grow I did was a 1m/1m/2meter grow tent and I used a 4 in. squirrel can fan (can't remember how much air it pumped) and I spent my time wishing I had just gone with the bigger 6 or 8 in. version that pumped more air. So I was considering a big one. I have used an air cooled sealed hood in the past but I have heard negative things about the loss of intensity caused by the glass so will probably not do that this time unless it becomes absolutely necessary for heat issues. If needed I could buy 2 one to exhaust the air from the room and one strictly to pull fresh cool air from outside in through sealed air cooled reflector hoods then exhausted back outside. I would prefer not to have to do that though.
Question 2 is about the soil beds. What depth of soil would you recommend for this style of grow? I was thinking maybe about 14 in. of soil depth? If I could get away with less that would be better but def not going to go any deeper than 18 in. no matter what. What kind of spacing for the plants in the bed? My thought was 1 per square ft. so 4 rows of 4 in each bed. Should I do more or less or is this a good range to start in and adjust it as needed for the strains I'm growing?
Question 3 is about my electric choices. I plan to have each 1000w light to it's own dedicated 20amp breaker. The exhaust fans will be on another 20 amp. The couple/few internal fans will be run off a couple outlets already wired into the space on a shared 15 amp. All the outlets will be GFI ones. Next spring if I need to put in an ac I will probably run another breaker for.
I'm sure I will have some more questions but just overall anyone see any glaring issues that are going to smack me in the face. Any better ideas than what i'm planning? I guess lastly am I wasting my $ on HPS are the LED comparable these days in actual grams per meter squared? Or am I still best just getting the HPS. Maybe use an led in the middle of the 2 soil beds so they get better full spectrum light but still get the dense buds and good yield of HPS? Thanks for the advice in advance.
 
I think I'd go with an 8" or 2 6" centrifuge type fans for that space. Get fan speed controller(s) and I think you should plan on using a filter. Venting out the side of the house will present special problems, you may want to consider other options. It can be hard to keep the weather out.

I see no advantages to 4 x 4 soil beds, but a lot of disadvantages. First, it will be very difficult, if not impossible to reach the plants on the far side of the beds and take proper care of them as you will only have access from 1 side. It will be hard to waterproof everything so you do not end up with runoff all over everything. I think that 1 plant per sq ft is too crowded. It is detrimental to plant health and yield to overcrowd them. There are other downsides. I would recommend individual 5 gal fabric bags with drip trays.

I never think it is a good idea to have all the exhaust fans on 1 breaker. You can put a single 1000W light and a fan on a 20 amp circuit without any problem. I believe this is a better set up and you can use 2 20 amp circuits rather than 3.

If you go with HPS lights, I don't think you can keep things cool enough without the glass. You can probably use a passive intake system. The intakes do not employ the use of a fan. Air is pulled in passively by the action of the exhaust fan pulling and pushing air out. When using 2 lights and 1 fan, I generally hook them up in parallel rather than in series.

Good luck with your project. It is always fun to set up a new space.
 
Don't know much, sorry I can't give you any useful advice. I haven't used the HPS lights, I use the white led, bring the full spectrum light, now it seems that the LED is the future. Good luck,I will keep following it.
 
BTW, I use 2 units SP 250 from Mars Hydro for my 4ft/4ft tent, you can take account into it
 
Thanks for the responses. There were a couple reasons I was thinking about the soil beds over individual buckets. I wanted to maximize the amount of root space. Individual buckets even square ones leave lots of unused airspace between them. I haven't thought of the fabric bags though maybe they would be a bit better than pails. I would have access on multiple sides and be able to rotate the beds but you are def correct that it wouldn't be very easy. I plan to do a Sea of Green grow. I plan on using clones, giving them at most a few weeks to root and veg then immediately flowering them. My hope is to keep the plants short hopefully about 3ft at their finish. Also don't want to waste time and money vegging big plants would rather just flower a bunch of smaller clones. That was one reason for the short spacing on them 1 per square ft might be too crowded though even for that plan. If I was to use pots yet still keeping to my SOG plan would you still recommend the 5 gal size ones? I want them to have enough root space but be as efficient as possible. Maybe one option would be to do one half of the room under 1 light SOG and the other half regular size plants in 5 gal pails. Then I could see which one is the most efficient for me. I'm sure there was more questions I wanted to ask but my brain has stopped working correctly at this hour so i'm going to end it. Thank you for the help it is very appreciated to be able to bounce ideas off of some people.
 
Tell me why you want to use SOG? Have you grown this way before? Do you wonder why hardly anyone uses this growing method? There are truly a lot of pitfalls to running a SOG. And not a lot of upsides. Have you got a good source for that many healthy clones all the same size, age, and strain? What is the penalty in your state for that many plants? Many states have mandatory jail sentences for larger grows. They don't care that your 32 SOG plants may not yield what 2 well-tended, well vegged plants may produce. Plant count is always something to keep in mind. When I lived in Idaho, I never had more than 25 plants going as that was a mandatory jail sentence.

Soil beds that are 4 x 4 and 14-18" are going to need to be stationary--you are not going to be able to move or rotate them. And you cannot rotate a 4' square in a 4' wide room. The weight after watering will be horrendous--you may actually have to reinforce your floors to accommodate them, unless you are on slab. Think of it like a water bed, only heavier as it is deeper(thicker). I can hardly drag 25 gallon bags when they have plants in them. It can also be very hard to make beds like this 100% water tight. It could leak under the beds the entire grow and you might not be aware of it until harvest....or until the floor starts getting soft, smelly, and rotten. If it starts leaking partway through your grow, it will be virtually impossible to move the plants as their roots will all be intermingled. Likewise, if a plant has disease or dies, it will be hard to completely remove it without damaging the roots of the plants nearby. I've never been a fan of multiple plants in one pot/bed because of this.

You really will not be able to do half and half in the same room as you will want to give the non-SOG plants some time to veg. I really like at least a 6 week veg, but usually actually went about 8 weeks as I ran a perpetual harvest. It is not a waste of time and money to give your plants a decent veg time. All the time they are vegging, they are growing and producing more bud sites. SOG plants often yield only 1/4 oz or so. A well vegged, well tended plant will produce 3-4 ozs indoors (depending on strain of course).

We all want our grows to be fruitful and productive. But unfortunately, after decades of growing, I have found that there are really no shortcuts. No one growing method that outshines the others. No method that is going to get you more faster. There are of course, some things that work better than others. And everyone has their own favorite ways methods of growing. No 2 grows will every really be identical. If you decide on SOG, I encourage you to rethink the soil beds--too many potential serious problems. The fabric bags come in all sizes and you can put them fairly close together (but you do want some room around them). You will need some kind of drip tray with them, as you need with all kinds of pots.

I have a 768W and a 700W LED (different brands) that I do not feel is enough light for my 4 x 4 tent. Hamster Lewis is using King LEDs that he is very happy with. You may want to check his threads/grows out.

LOL--sitting here drinking coffee with a bit of Irish Cream and toking on some great Satori...got a little long-winded.
 
Soooooooooooooooo what would be a good sized area per plant? Say for a plant to grow 4 to 6 feet tall.
 
Thanks for the response. After thinking about what you said for a while mainly "why do I want to grow SOG" I think I can finally answer. Basically I had a buddy who grew like that and it just seemed really slick. Really quick turn around time from harvest to flowering again. I think it made an impression on me and has influenced my decision to want to grow that way. However you made a lot of great points and i'm not dumb enough to walk away from advice from someone with a lot more experience with me. So I will scrap that for now. I will try the soil bags you recommend. Still not positive if I will use 3 or 5 gallon bags i'll let the plants tell me I guess.
I have come across an issue though so I have a couple more question. I had some spa test strips so I decided to check my water to get an idea where it's at. The PH was darker than the 7.6 but lighter than the 8. Also the Alkalinity was off the chart darker than the darkest mark which was 180 ppm. This is well water. It's not town water. I do have other sources for water which I plan to test. Also I know these strips aren't exact I will be getting a PH/EC/PPM meter soon. This is the water source at the grow site though. Other water would have to be hauled in as oppose to turning on a faucet. So I guess I could get the ph into range but what about that alk it's very high. Is that a problem? If so is there a way to fix it?
Secondly I have a quick question about lights. I'm going to use what I currently have instead of buying more for my first flowering. I have a 1000w hps and 2 400w HPS/MH. My question is about light spectrum. Should I go with mh lights for the 400w lights? Should I just use HPS and call it good? Or should I use HPS lights and add some t5 or led side lighting? Basically I was under the understanding that a full spectrum light got you frostier buds (helps with resin production) or that's what I have heard. Is it true or mostly hogwash and just best to stick with HPS? Thanks for all the help.
 
I mainly wanted you to give it some real thought. We all see things that seem real cool, but have hidden pitfalls. The jail thing really cooled my jets.

What are your thoughts now? Do you have a source for rooted clones? If you use clones, you can still do a shorter veg time and flip them when they are the size you want. They will continue to grow some the first 2 or 3 weeks of 12/12, but then not get much bigger as they start putting weight on the buds. Have you thought about your soil mix or nutrients?

You should have your water tested to find out exactly what is in it, but you are probably going to need to use a filter or (more probably) an RO. Well water usually (but not always) has a lot of dissolved solids that need to be removed. Your pH is high because your alk is high. You will control your pH with pH down (or up, but usually down). Be sure to get calibration liquids if the meter requires them. If you are considering another water source, have it tested, too. It is fairly inexpensive and most county extension offices do it or can refer you to someone.

You are going to want to use a blue light source for vegging. It may be that the 2 400W MH will be enough as vegging plants are smaller than flowering plants. I really can't answer your question about a mixed light spectrum. I hear differing things. I've never been a fan of side lighting. When I grew in a closet and tents, I usually filled the space up with foliage and had no room around the edges for lights. If you have a T5 though, it would be good to use during vegging along with the MH. I actually use just T5 for vegging now rather than MH.
 
Hey I might not have time for a full response i'm on my lunch break. I have a small space I'm going to use to hold small mother plants in veg. I will clip clones and root them right before I harvest my flower room. Then after harvest move rooted clones into the flower room to veg for a short period before flipping to flower again. I don't currently have t5 lights. I was more asking if people thought it was worth the extra effort to add more full spectrum light via t5 or led. The HPS would still be where I was getting the majority of the light the others would just be there to help round out a more full spectrum light. However when I last grew I had good results with plain old HPS.
I will be vegging with the mh 400 for now. I was considering maybe just flowering with the 400w mh to save me the $ on the extra HPS lightbulbs as my ballasts fire both. Also I was curios if it might give them a more balanced spectrum of light having the 1000w hps and both 400w using the mh. Although I feel as though I might be high and overthinking it...
I have to get back to work but I will post up and talk soil when I get back. I currently have some clones in Fox Farm Ocean Forest but I was going to use Pro Mix when I repot them. Do you have any favorites or suggestions on making a mix? I have a set of fox farm nutes but am considering buying a set of something else.
 
I really don't know if there is a benefit in adding/using blue light during flowering. I really couldn't find anything not anecdotal that supported that theory. I have heard that other light, like ultraviolet can help with resin production later in flowering, but I have not tried it. Also, I don't know if it is significant or not, but MH bulbs do not put out as many lumens as HPS for the same electrical usage. And I know that oftentimes money is tight, so if HPS bulbs are not in the budget (though you do have a couple of months and they aren't too expensive), you can flower with the 400W MH and the 1000W HPS.

I used to get a base soil from Home Depot that I liked. But I am now 1-1/2 hours way from a HD, so went with a different soil. I found a Whitney Farms product I like. It is an organic soil for raised beds. I use 1 part of that, 1 part peat moss, 1 part perlite, 1 part compost or worm castings. To that, I add a few amendments--soybean meal, kelp meal, lime, rock phosphate, and greensand. For each 8 gallons of medium, I add 1/2 c each of amendments. Do you have the Grow Big, Tiger Bloom, Big Bloom trio? Fox Farm makes a fine soil and good nutrients.
 
I just want you to consider LED's. They are so much cooler, i started with HPS and MH, and had the ducting and all that...now i have an led, a small fan. that is it. Just a thought.
 
Yes I have the Fox Farm Trio and the Ocean Forest soil they make. However last time I grew I used the same soil and I felt like it needed better drainage. Was considering adding some extra perlite to it to achieve that. I also was considering a few soil amendments such as guano, worm castings (which i'm making myself I fish a lot and have a big worm cooler I fill with beautiful top soil from my families maple woods), bone and blood meal possibly. I also like Kelp a lot but in the past I used it in a liquid.
I am considering going LED but not for a grow or 2. I currently have the ballasts and reflectors just have to get the bulbs. So it's too cheap to not go that way. But will most likely try to little by little change the HPS lights over to LED. What LED would you suggest to try to replace a 1000w HPS with?
 
Adding perlite will improve drainage, so go ahead and add some if you feel you need more. It won't hurt anything at all. It is probably best though to not just indiscriminately add amendments. I suggest finding a recipe online somewhere. You don't want to overload on any one nutrient. Like if you use high N guano, you probably are not going to want to add high N blood meal. Worm castings are always great and they are a great ingredient for nutrient teas. It sounds like you could be growing organic. You may want to set the Fox Farm nutes aside and go organic.

Rosebud is so right about the heat from HIDs. But...I still grow with HPS. In the winter, the heat is an asset. I blow the filtered exhaust into our living space. In the summer, I grow outside. Not pooh-poohing LEDs--I have 2 LEDs. And only budget constraints have kept me from buying newer/better LEDs (sounds like you are in the same boat). LEDs have gotten a whole lot more affordable though. There are many here using the King LEDs and getting very good results. Unlike HID lighting where bigger is better, people usually use more, lower wattage LEDs. One thing to keep in mind is that the wattage on most LEDs is not the working wattage. A 1000W LED does not use and put out 1000W of light. So you generally cannot replace a 1000W HPS with a 1000W LED. When you get ready for LEDs, you can ask the people for their suggestions.
 
How often should the air in my room be replaced? Just trying to figure out what would work well for an exhaust fan. Also what way do the can fans work best pulling air or pushing it? Like should the fan be at the end or beginning of the run of hose? Or should it be in the middle? Thanks for the help.
 
I personally like to exchange the air in my space several times a minute. I used a 6" 450 cfm Vortex for a space that was 3 x 6.5 x 7.5, so...a little under 150 cu ft of space. You have 280 cu ft. If you have the fan pulling air it creates negative pressure and helps keep any odors in the room contained. If you have it pushing air, it forces air from the grow room into adjoining spaces. You my find you do not even need an intake fan. There are several ways you can set your ventilation up. I had ducting connected to my light hood (which has glass), which was connected to my exhaust fan. The fan can either be located within the grow space or someplace outside the grow space. I have at different times had it located in my crawl space, in the tent, and beside the tent. They do make some noise, so that will influence your decision.

Is a can fan a brand name? Or a certain type of fan? I am not really sure what kind of fan you are talking about. You are going to want a centrifuge type fan, like a Vortex, not a duct booster fan (which kind of looks like a can).
 
centrifuge type fan is what i'm using. It's a 6in. active air brand fan 400cfm. So it will be a bit under twice a minute. I plan 0n using a passive intake. As well as a couple fans circulating air around the grow room. Seems like the fan will do best set up pulling the air. It will be pulling air from the room into my 1000w lights sealed hood then exhausting it outside. Hoping that will be enough to keep my room cool enough. I can pull in fresh air from outside easily and it's plenty cold here 3 of the 4 seasons. If need be I will get a second fan to exhaust more air but hopefully this will work fine.
 

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