Dr. Conrad
Active Member
homebox xs measures 2'x2'x4'. will i be able to have two foot tall plants in there without burning?
is a 250w HPS to hot for a Homebox XS?
- Thread starter Dr. Conrad
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Syriuslydelyrius
Well-Known Member
Run a good enough ventilation set up and you could burn a huge bulb in a small area. The lower the watt HID lamp the closer to plants can go. There is debate over how many lumens per sq you should have but still many would consider the 250w to be over kill in that small area.
250w =25,000 lumen = 6250 lumen per sq ft
150w = 16,000 lumen = 4000 lumen per sq ft.
Either would be plenty fine and the 150w would be easier to cool in there.
Dr. Conrad
Active Member
Well about how hot will the 150w get? what sort of measures should i go to to keep the temps around 78F?
Well, if you consider that fact that your planters will eat up about 6"-8", you have to subtract that from the 2' you have left. That leaves about 1 1/2' left. Your light hood, depending on the make, could take up another 6"-12". Now, I don't know what your growing experience is and I don't want to offend, but, I've NEVER been able to keep a plant that short. (most likely my own problem) That leaves you about 6". Not a very good distance for 250 watts. I'd go with the 150 watts. I use a 250 watt and my closet is 5' tall, and that's ALWAYS pusing it. Even with LST.
If you didn't already buy a Homebox XS, you would always buy a Growlab 60 they look pretty good, have the same specs as the Homebox XS but has a height of 5'3 which could help on height issues. Growlab clams the Growlab works nicely with a 250watt HPS or 400HPS watt HPS, so it seems to be a better deal for you.
Flo Grow
Well-Known Member
Actually, a 250w would be PERFECT for the XS. I have the XS and currently run with a 150w HPS Sun System. I have a weak 65cfm 4" fan for exhaust and my temps stay around 83F. I'm upgrading to a 250w HID and a 170cfm 4" fan for exhaust.
Again, my 150w Sun System isn't "air-cooled", and I stay around 83F, which is still a VERY safe temp.
I currently have 2 females that are now on Day 35 flower today. My pots are 7.5"L x 7.5"W x 9.25"H, which equals exactly 2.25 gallons. My plants are 15 and 17 inches tall respectively, while being 3 inches under the 150w with NO HEAT ISSUES and it's NOT air-cooled either. My fixture is 5" tall + 3" from light + 9" from floor to top of soil = 17 inches. So 48 inches minus 17 inches means I can MAX my plants to 31".
Calculating a 3x stretch ( to be safe), veg until 10" tall MAX (8" to be safe until you DIAL IN/KNOW your plants stretch) equals 30 inch tall plants. I flowered mine at 6" tall and 21 days old from seed.
Check around, you'll see plenty of cats running a 250w HID in this approx size area with OUTSTANDING results. ESPECIALLY is you learn how to SCROG !! You'll be looking at 4 - 6 ounces per harvest once you learn the technique efficiently, as well as your plants. Then the 4 foot height restriction WON'T MATTER AT ALL. Seen one grower (on here or ICMAG) get over 12 ounces in a SCROG with ONE PLANT (Querkle) grown in an 18 gallon rubbermaid, but veg'd for about 2 months too !!!!!!!!
Here's some additional info to help:
p.s. To view the Ventilation chart, I suggest opening it with Microsoft Paint or Picture Manager so you can increase the zoom.
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Flo Grow
Well-Known Member
Here's how you calculate the Ventilation !!!!
Here’s how you can calculate the amount of ventilation you will need. If for instance you wanted to keep your grow room temperature from getting any more than 5° warmer than the intake air temperature, and you were using 250 watts of power, you’d make the calculation below. The info is based on the following formula from the Home Ventilating Institute. It is a well-established heat transfer formula.
CFM = 3.2 x Wattage / Difference in Temp
So 3.2 x 250w divided by 5 (grow room temp increase over ambient temp with lights on) = 160cfm
You can also substitute your current fans cfm with Diff. in Temp to find what your grow room temps will average.
Case in point, my ambient temps are 76F with lights out.
So: 3.2 x 150w / 65cfm = 7.38 degrees
and 7.38F + 76F (ambient temp) = 83.38F = 83.4F
For those wondering, I forget what the 3.2 represents. It's actually 3.16, rounded up to 3.2, which gives you a SLIGHTLY higher cfm rating. Being slightly higher actually gives you more room for error on the SAFE SIDE.
PEACE
kaptainchron420
Member
so here's one for ya... i recently redid my garden and switched from soil to hydroponics.. i have a 2x5x5 clone/mother room with 6 4 foot cool flourescents.. my veg room is 5x6x7 with 4 sunleaves satellite iv flourescents.. my flower room will roughly be 7x8x7.. once its actually completed ill post pics.. but its all covered in black and white poly.. nicely sectioned off.. air tight... one 400 cfm (roughly) in each the veg and what will be the flower room... plus a 16 inch air king fan in both.. a can 50 with HO 6inch fan for smell... will have 2 ebb and grow systems (one for each cycle obviously)... its a really nice half way done set up.. should only take a week or so to finish.. right now tho i have some soil plants that i started flowering on the veg side.. they are under bloom bulbs.. i mean.. i spent almost 5 stacks already.. didnt have enough for the second ebb and grow or more flowering lights.. so once i have another 3 stacks or so ill finish it out.. basically i have one room set up and need more money for a second ebb and grow and lights before i can have it all up and running.. my question is this.. think 6-600 watt hps bulbs on electronic ballasts will be "too much lighting"?? using the 50watt/foot i only need 2800 watts.. but.. i really want to cover the garden well.. and i wont go with 1000 watt.. too inefficent..
C
chitownsmoking
Guest
DUDE that area would be ideal for a 250 watt hps. i use a 250 also.with a good fan i can get it to arround 3-4 inches away from the topsof my plants w/o a cooltube but this is in a more open area unlike a box so i would suggest strongly you use a cool tube, and paint the inside of the box flat white for better reflection. a 250 watt light is a decent light. it will kill any flouro at 28,500 lumens. and i got mine for just over a hundred dallars. try to keep your plants at around 2 feet because that is about the maX that a 250 can properly penatrate s like 24-26 nches. and keep in mind the further the light frm the plants the less lumens they recieave. so train your plants to be short, and keep the light on them close. i think you will be happy with your results. i recomend l.s.t. or a nice scrog
Flo Grow
Well-Known Member
If your flower room will be under 3,600 watts, then:
3.2 x 3,600w = 11,520 divided by 5 (temp increase over ambient temps) = 2,304 CFM's OR 384 CFM's per lights
3.2 x 600w divided by 5 = 384 CFM's
It's not an actually BOX. It's a grow tent called the Homebox, and he has the smallest size like me that's called the Homebox XS (extra small).
Your right about the 250w light penetration though. Which is why ppl are getting 400w and 600w size harvest from running a SCROG with just a 250w HID. The plants will grow approx 8" to 20" above the screen, depending on the growers skill level and the strain of MJ involved.
Flo Grow
Well-Known Member
Check this out fellas ! I got the chart to work correctly.
Also for coverage info:
150w = 1.75 foot x 1.75 foot
250w = 2.25 feet x 2.25 feet
400w = 3 feet x 3 feet
600w = 4 feet x 4 feet
1000w = 5 feet x 5 feet
Each of these lights will cover a SLIGHTLY larger area, but to get THE MOST use out of each one, the listed areas are more ideal.
Also for coverage info:
150w = 1.75 foot x 1.75 foot
250w = 2.25 feet x 2.25 feet
400w = 3 feet x 3 feet
600w = 4 feet x 4 feet
1000w = 5 feet x 5 feet
Each of these lights will cover a SLIGHTLY larger area, but to get THE MOST use out of each one, the listed areas are more ideal.
