HPS kit from hi-tech garden

Hey folks


trying to decide on the best lighting for my project. I have a small grow box made of plywood with an open back (the room wall is the back so I can just move the box out for easy access - was too lazy to build a door). It's 4' high, 4' wide, and 2' deep. I'm looking into buying a HPS system that's for sale from High tech garden supply. It's 120 bucks for a 400 watt ballast, reflector, hanger, bulb, the whole shebang. My question is, would I be able to successfully mount such a contraption to the rather flimsy top of my plywood grow box? I have a small fan and I live in a place that's cold as shit (think VT = canadian border) so I don't think excess heat will be a problem. My other option is to just go with a five-head floor lamp and use y-adapters to get ten 30-watt fluorescent bulbs going (6400 k for veg).

For two plants in a 32 cubic foot box (with whitewashed surfaces), I would get 50,000 lumens with the High pressure sodium system, compared to 20,000 lumens with 10 CFL's. So is the HPS system feasible with my setup, and would that amount of light be necessary for just two plants? Thanks much for any help!

Peace,

J

Hi VT, welcome to the forum. :thumbsup:

Both HPS and CFL will work, I personally would go for the HPS though, but thats down to personal preference. You may need to strenghten your grow box, but thats not a bad thing to do anyway. You will need reasonable ventilation whichever way you go as both type of light will put out a lot of heat (even in your cold climate) and you don't want a plywood based open fire in your house! I notice you say you have a small fan, is this for circulating air inside your box or for extracting stale air and drawing in fresh air through your box? You will want both for the best effect (fresh air = more CO2 = better growth).

6400k CFL's are great for vegging though.

A 400w HPS would be a nice size light for your area (8 square feet). Don't worry about cubic feet, it's the footprint that's important because you will have the ability to move the light up and down, thus rendering the third dimension obsolete.

If you can post a pic or two it would be helpful.. good luck :thumbsup:

Hey thanks so much for your help. I don't have the box all done yet, it's just the frame but without ventilation or wiring holes cut into it yet. I'm currently just vegging in my room but it's time to finish this better setup. I'll snap a photo or two once I get it all set up. I'm thinking I'll have the fan blowing through a hole in the grow box so that it moves outside air around the canopy of the plant. Sounds like a good call to have one blowing stale air out as well, so I'll probably pick up another desk fan and set that up inside blowing out another vent hole. It sounds like the HPS would work with this weight-wise, I'm just wondering if it would be possible to have the plant canopy far enough away from the light in a four-foot high space. Assuming the plants grow to a solid three feet, that doesn't leave much room for the light to hang, right? Wouldn't wanna burn my precious plants! Thanks again, loafyboy!

I'm tellin u this now so u dont have to deal with it later, heat is going to be a problem for you. I had the exact same dimensions with a 400 watter and it was in the high 90's all the time with a sufficient fan pulling air out of the box, the key to doing this is going to be a cooltube or something similar, and venting somewhere the heat has to go. I wound up destroying the box cause my plants were getting to hot and just outgrew it.

Personally, I would make the box a lil taller. Depending on the strain ur plants might outgrow it, and if ur only growing 2 plants cfls will work plus keep ur electric bill down. my frirst grow, i grew 3 plants with only 4 150watt equevlant cfl bulbs . yeild was about an ounce per plant.

hands down a hps lamp will out perform a cfl any day of the week "not to offend the cfl growers, u do good work!!" the box in height is 2 small and your really going to be kicking your self later.5 to 6 ft is optimal "it also gives the heat a place to go to thats not right at the canopy.my suggestion,buy the hps lamp buy a decent cfm fan and some exhaust tubing.vent the light with the fan pulling the air through a filter and out of the house.drill several 4 inch holes at the bottom side panel of your box 4 or 5 it perfect.at this point u wil have fresh air from the room your box is is full of usable natural co2 and u have solved sent and light heat issues all with one fan.post some pics of your setup!!

I don't think I'll be able to cut a vent hole out of the house. That's just not possible in my living situation. However, where I live the temperature is often around 0 degrees fahrenheit outside during the winter, so even cracking the nearby window a tiny bit would cool the plant off enough I would think. We're talking serious cold, sometimes 15 or more below zero. So, based on your suggestions I think I'm gonna do the following:

Extend the height of my box by a foot or two (I have to check what's the tallest I can make it).

Cut a couple of holes toward the bottom of the box for intake

Cut another big hole for my clip on fan to exhaust through, this one near the top.

Buy a wall mount oscillating fan and set that up inside as well.

Buy the HPS light kit with metal halide conversion bulb and mount that to the 'ceiling.'


The external room is a bedroom, but its occupant (my partner in crime) is very cold tolerant, so if the room is kept at 50 degrees (still major heating compared to 0 degree external), I would think my plants would be amply cool, no?

My only problem now is figuring out how to have ventilation without light leaks. The most light that is ever on in the outside room containing the grow box is a computer screen, but still, during flowering some of that light would have to penetrate through my ventilation holes, right? how do you folks manage to ventilate your grow spaces without creating potential light leak problems? Thanks for reading and any advice, again, much appreciated.