Box building questions

[Jaxom]

I was going to build a smaller box, but have decided to go with something just a bit bigger then a smallish box with a 150hps.

New new design is 7' tall, 4' across and 32" deep. Very basic design, just using this box for my flowering chamber. Instead of a 150hps, I'm going to upgrade to a 400.

Meathod of growing, sog, perhaps scrog.

Questions....

Although though the box will be 7' tall, figure the top 12" will be where I stash the ballast and have a charcoal filter. Although I'm making the box 32" wide, with some creative woodworking I'm figuring a grow area that's 48"x30" or 10sq ft. This keeps my calculations very simple...
This means I have 60cubic feet. What sized fan should I be looking at to vent this with? I plan on using a panasonic whisper fan, just need to know what size rating in cfms. Before suggestion, read my next question about lighting.

I can get a 400w hps for $105 from econolights and build my own remote ballast and reflector. Even with the added parts, this would still be conciderably less expensive then going to a hydro store. But at 10sq feet, that only gives me 40w per sq ft. Is this really enough? Unfortunilly, econolights.com doesn't sell a 600, 800 or 1000w hps's. I could add a couple 100w mh's for a broader spectrum, but I'd need to know if I'd have to get a larger vent fan now. Suggestions?

I use to grow sog style, at a commercial level, many years ago. There's been alot of advancements in style of growing and such since then. I've always been interested in doing a scrog for a smaller personal grow as this will be. The main reason I decided to jump from a 150hps to a 400, is so that I have enough crop left over to make some bubble hash. Since I don't have experience with scrog, what is the average yield per square foot on a well maintainted dwc style scrog?

Thanks,

Jax

 

[Jnugg]

The measurements you gave would give you 10.66 square feet to work with therefore I would strongly recommend a 600w HPS/With only a 400w HPS over a 10.66 square foot area you'd only be providing the plants with 37.5 wpsf and only 4687 lpsf...with a 600w HPS you'd get 56.25 wpsf and about 8,437 lpsf...recommended minimum for fat healthy buds is 50 watts per square foot and you should try to provide 7k-10k lumens per square foot.

My vote is scrap the 400w HPS idea and purchase a nice 600w HPS!


As for ventilation and scrubbing/de-odorizing the grow it really depends....1)what are your ambient temps (temperature of the air the grow area sits in...2)how many degrees above ambient would you like the temps in the grow to be...3)Are you wanting to use one fan to both cool the light and exhuast/de-odorize or two fans one being dedicated to just A/C the light and one designated to ventilate/de-odorize?

I'd think a 6" 300-440cfm inline centrifugal (vortex,eco plus,can fan,elicent etc) would be the route to go although you may want an 8" inline centrifugal depending on the filter you use and how much airflow you need to keep things cool.

 

[ItsAllOver]

Listen to the guy above.
I say you need a 600w light, as well. You'll be disappointed in the 400w I'm afraid.

 

[fatigues]

There is another option I thought I might draw to your attention.

You could choose to get a Galaxy 250w Dual e-ballast, and run 2x250 in that space off of just one ballast. Penetration to lower foilage is theoretically a little weaker than with a 400 on a few of the plants - and probably is actually weaker than a 600 with a third of the plants or so, but your coverage in terms of square footage on the overall main colas will be much improved as you have two focal points, not one. More imporantly, your distance from the tops of the plants will be significantly better as well as there is less heat and two origin points for the light, not one.

You can even run the dual 250s through the same cool tube, and your total costs for doing this is about the same as a single 400watt in terms of equipment outlay. Increased energy cost is minimal.

Only real problem is if you wanted to use CMH. A Galaxy dual e-ballast is not compatible with CMH. If you are fine with MH and HPS - this approach is also viable for you and presents a mid way point between 400 and 600 watts.

If CMH is an issue, there is nothing preventing you from picking up 2 magnetic 250 ballasts. They tend to go for pretty cheap, especially if they are used.

 

[Jaxom]

Ah, first of I was going by 10sq ft. Yes I said 32 deep, but I'm not counting 2" for some "creative light sealing" that I have planned.

I was afraid someone was going to say 600 was a better way to go, but that would mess up my rather limited budget. Example, the cheapest 600w hps I can get locally is $265 plus tax and shipping. If I order the 400hps from econolights.com that's only $105 plus shipping. I can start out with this and then add two 100w MH's for a broader spectrum. I do realize this arrangment won't be as intense as a single 600w hps. But sometimes you have to deal with a bit of give and take. I'd really like to hear from someone who's ran a dwc scrog setup under these conditions. I have yet to call or talk to any electrical supply houses in my area, there's two not to far from me, and I can see if they have a 600w security lamp that would suit my needs but doesn't break the piggy bank too much.

The box is going to be stealthily mixed in with my basement workshop. With a 6yr old child running around the house, I don't want to take any chances and have all my shop related chemicals (stains, paints, glues, ect) along with my reloading supplies in other cabinets all with hasps and pad locks on them.

Our home is brick and the basement is 4' below grade, so it remains rather cool, even through the hottest part of the year. Although it's never really cold either. So I don't think I'll have much of an issue with over heating. I do undertand it's not just only cooling but bringingi fresh air that helps plants thrive. Remember I have grown before, just on a much larger scale. A friend of mine who trusts me, and I trust him has a stealth box running a 250hps. He's using a 110cfm panasonic whisper. NICE unit, you can't even tell it's working!

Then when I came across this link I was sold on doing this....

http://www.icmag.com/ic/showthread.php?t=45196&page=1&highlight=carbon+screen

Online I found a 380cfm version of these fans that runs at 3 sones (very quiet!), for $225. I may have to adjust the top shelf a bit since it's 17" wide, but still, I think it'd be worth it. If I mount it right, I can scrub the air from the flower chamber below and keep my ballast(s) cool.

I'm still confused though as to which would be best. I realize that a single more powerful lamp will emit more intense light, but only within a limited spectrum. Where as I could get a wider spectrum using a combination of hps and mh. This is where I think someone that's ran a scrog cabinet can be really helpful. My intent is to grow mainly pure indicia's. Any day of the week I can get my hands on good satavia or satavia/indicia crosses, why repeat these? Eventually it's my hopes to set up a breeding/cross breeding program to design my own special "hash plant". The MH spectrum would help to keep my plants nice and squat sized, while at the same time the 400w hps would make them really dence and tight. See my dilema?

Jax

 

[Jaxom]

Now see, this is what happens when life interupts...what's a CMH? Please explain.

Thanks

Jax

 

[etinarcadiaego]

I've grown LST in a closet of a similar size, I'd suggest a 600 Watt lamp as well. You don't need a MH and an HPS in one room in my opinion, using a more powerful (and efficient) single light source will suffice . . . And multiple reflectors gets to be tricky.

A CMH is a "Ceramic Metal Halide." Check this link out: http://icmag.com/ic/showthread.php?t=72215

My plants grew nice and squat and dense and tight all from one 600 watt HPS. I also ran it in a basement, and beware of RH, mine ran high (70-75%) which causes serious mold issues late in flowering.

I don't know anything about a whisper quiet fan, but I ran a 6" centri fan and it cooled the light well, but was VERY loud. This has been some years ago . . .

 

[fatigues]

The general concensus on fan noise among most ICMag members is that the S&P inline fans are as quiet (and in the opinion of many ICMag members, even quieter) than the Panasonic Whisper fans. A good discussion of S&P fans by ICmag members can be found here.

The S&P fans are also cheaper, smaller and easier to install. Unlike most of the Panasonic Whisper fan line, the S&P fans also can use standard Carbon can fan scrubbers. (Given the intake and exhaust port sizes of most (though not all) of the Panasonic Whisper fan line, this is not possible on Panasonic fans.)

The S&P fans are, in terms of their construction, a hybrid design and are very quiet when used with a fan speed controller. You can order S&P fans here on HVACquick.com's website.

Note: while it is not exlained on Hvacquick.com's site, they will ship via USPS upon request -- just send them an e-mail to request it. (This is the preferred shipment method for customers in Canada or for those who wish delivery to a P.O. Box).

 

[fatigues]

Now see, this is what happens when life interupts...what's a CMH? Please explain.

The CMH thread is a monster. Suffice to say that CMH stands for Ceramic Metal Halide and is a relatively new bulb manufactured by Phillips that is particularly well suited to growers with an astounding spectrum and relatively strong light penetration. Results for the CMH by most growers on ICMag exceed results over those who use normal metal halide bulbs or HPS - or both bulbs - during a grow.

CMH is a full spectrum grow light, so you use the same bulb for both vegging and flowering. Needing just one bulb is nice - although the mileage put on the bulb over the course of one grow does accumulate faster than if you were using a MH and HPS for a grow.

CMH bulbs also effectively run cooler than metal halide bulbs, in terms of how they shed heat off of the bulb fixture itself. For some cabs, this is an important feature.

The maximum wattage for CMH bulbs right now is 400w. There are no 600 or 1000 CMH bulbs yet. The bulbs do come in lower wattages, but typically, people are using 250w or 400w CMH bulbs for a grow.

(Note: pulse start metal halide bulbs are different than CMH bulbs).

The design of Phillips' CMH bulbs are such that they do not operate properly at high frequencies. Nearly all Electronic ballasts operate at much higher frequencies than do the older magnetic core ballasts.

Unless the electronic ballast specifically says that it works with Ceramic Meral Halide (not simply "works with Metal Halide", and not "pulse start metal halide". It must say works with CMH specifically, on the ballast details) it should not be used with such a ballast, as that can cause it to fail to operate or explode. An exploding CMH bulb would be very, very bad and could burn you, blind you, or start a fire - or all three, for that matter.

When I last read the monster CMH thread, the only e-ballast which worked with CMH bulbs was created by General Electric. None of the standard electronic ballasts aimed at the uhm...."hobby market", shall we say, work with CMH bulbs. So Galaxy, Lumatek, Quantum, and Next Gen e-ballasts are not going to work with CMH bulbs. (The fact that the Galaxy Dual 250w e-ballast won't work with CMH is particularly annoying, in my case.)

Ironically, CMH bulbs, as the new kid on the block, work extremely well with old style iron core and coil magnetic ballasts. If you want to try a CMH bulb, odds are good that with a little patience, you can pick up a used magnetic 250 or 400 watt ballast on your local craigslist for pretty cheap.

 

[Jnugg]

Ah, first of I was going by 10sq ft. Yes I said 32 deep, but I'm not counting 2" for some "creative light sealing" that I have planned.

I was afraid someone was going to say 600 was a better way to go, but that would mess up my rather limited budget. Example, the cheapest 600w hps I can get locally is $265 plus tax and shipping. If I order the 400hps from econolights.com that's only $105 plus shipping. I can start out with this and then add two 100w MH's for a broader spectrum. I do realize this arrangment won't be as intense as a single 600w hps. But sometimes you have to deal with a bit of give and take. I'd really like to hear from someone who's ran a dwc scrog setup under these conditions. I have yet to call or talk to any electrical supply houses in my area, there's two not to far from me, and I can see if they have a 600w security lamp that would suit my needs but doesn't break the piggy bank too much.

The box is going to be stealthily mixed in with my basement workshop. With a 6yr old child running around the house, I don't want to take any chances and have all my shop related chemicals (stains, paints, glues, ect) along with my reloading supplies in other cabinets all with hasps and pad locks on them.

Our home is brick and the basement is 4' below grade, so it remains rather cool, even through the hottest part of the year. Although it's never really cold either. So I don't think I'll have much of an issue with over heating. I do undertand it's not just only cooling but bringingi fresh air that helps plants thrive. Remember I have grown before, just on a much larger scale. A friend of mine who trusts me, and I trust him has a stealth box running a 250hps. He's using a 110cfm panasonic whisper. NICE unit, you can't even tell it's working!

Then when I came across this link I was sold on doing this....

http://www.icmag.com/ic/showthread.php?t=45196&page=1&highlight=carbon+screen

Online I found a 380cfm version of these fans that runs at 3 sones (very quiet!), for $225. I may have to adjust the top shelf a bit since it's 17" wide, but still, I think it'd be worth it. If I mount it right, I can scrub the air from the flower chamber below and keep my ballast(s) cool.

I'm still confused though as to which would be best. I realize that a single more powerful lamp will emit more intense light, but only within a limited spectrum. Where as I could get a wider spectrum using a combination of hps and mh. This is where I think someone that's ran a scrog cabinet can be really helpful. My intent is to grow mainly pure indicia's. Any day of the week I can get my hands on good satavia or satavia/indicia crosses, why repeat these? Eventually it's my hopes to set up a breeding/cross breeding program to design my own special "hash plant". The MH spectrum would help to keep my plants nice and squat sized, while at the same time the 400w hps would make them really dence and tight. See my dilema?

Jax

first off,save up for an extra 2 weeks or month and then you can afford to purchase the 600w HPS.

You do not need an MH to keep your plants "squat".

That 400 is not going to give you dense tight buds...not when the plants are only receiving 37w per suare foot and 4690 lumens per square foot.

As far as spectrum...it has not once been proven that a mixture of MH & HPS make a difference.Years and years ago I did a side by side grow using the same strain in same sized floor plan with same wattage,only difference was one area was grown using an MH and one was grown using an HPS...the growth differences....NADA!

The only thing an MH offers over an HPS is more UV light which will supposedly increase resin/trichome production but I really doubt it will even raise that 5%.

If you're going to spend the money then don't you think you should do it right...the first time?!

 

[cork144]

just because he has 10sqft, doesnt mean he has to fill the entire thing with plants.

rockon with the 400 man, practice then upgrade to that 600

 

[Jnugg]

just because he has 10sqft, doesnt mean he has to fill the entire thing with plants.

This is true my friend,but the OP did not say wether or not they were going to utilize all of the 10 square feet or not so I went with the idea that they were.I agree if he sectioned/walled off an area that the 400 would do him great.

To the OP,how about a 3' x 2' area....IMO and IME it is best to provide atleast 50w per square foot and 7000 lumens per square foot,if not 10,000 lumens per square foot as the sun gives off around 15,000 lumens per square foot if I am not mistaken.