Lighting Heat Issues

MikeTarr

Active Member
Ok so my seedlings right now are starting to grow quite fast, and when the time comes to move to a better light(right now they're just under some cheap house hold flo's) I want to make sure I put them under a good light.


I wanted to buy this light:

http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=180136927343&ssPageName=MERC_VI_RSCC_Pr12_PcY_BIN_Stores_IT&refitem=120360918875&itemcount=12&refwidgetloc=active_view_item&usedrule1=StoreCatToStoreCat&refwidgettype=cross_promot_widget&_trksid=p284.m184&_trkparms=algo=DR&its=S%2BI%2BSS&itu=ISS%2BUCI%2BSI&otn=12

But I have a feeling it'll cause alot of heat and I'll have to buy cooling devices for it and that's getting too complicated for my situation here...Will this light create quite a bit of heat? Keep in mind the light will not be being placed in a small container or grow container or something, it'll be in a regular sized bedroom.


So if heat is an issue, I was thinking of purchasing this light:

http://cgi.ebay.com/2-Lamp-2-foot-T5-GROW-LIGHT-with-MIXED-VEG-BLOOM-BULBS_W0QQitemZ180194886614QQihZ008QQcategoryZ42225QQcmdZViewItem


Now I'm pretty sure there is a quality downside to these two lights? Or will they both work well? Just wanting your guys opinions. Thanks
 

Little Tommy

Well-Known Member
The first light should be fine for you. Just make sure that you have good air circulation and you should be OK. The second light would be good for veg, but that is about it. The first light will work for both stages, MH for veg and HPS for flowering and it is a very manageable size. Good luck with your grow.
 

MikeTarr

Active Member
Well the second link says it comes with 2 sets of the lights, it says:

[FONT=Arial, Helvetica, sans-serif]TWO 2' High Output 3000K BLOOM BULBS and TWO 2' High Output 6500K GROW BULBS Included
[/FONT]
One is for the veg stage and the other the flowering...Isn't that the same as doing the MH and HPS for the different stages?
 

MikeTarr

Active Member
Ok how about this? What if I purchase the 250 Watt HPS and MH? That is still a HUGE increase from the T5 lighting right? And probably cooler?
 

OregonMeds

Well-Known Member
It's just not close to enough for flowering though. If you want to flower a couple midget plants that give you tiny yields then yes, try flowering with only those t5 flouro's.

Nothing compares to a HPS, period. Oh and 250, well that depends. 250 is good for a 4 sf grow or so. 400 is good for 9 sf.

What you can do is grab a few standard incandescent bulbs and stick them in there. If you stick 400w of incandescent in there and can manage the heat with whatever exhaust you have planned then you're fine. If not, try less until it is ok. Watt for watt incandescent puts out the most heat so whatever works with them will work with the same wattage HPS.

Don't think you can get away without any exhaust or something... It doesn't matter even if you did just use the tiny 2' tubes you'd still have to vent the heat.
 

MikeTarr

Active Member
Well I can supply fans to circulate air, thats fine. But those huge fans that connect to the window and have large metal tubes that connect to the light and go to the window fan to circulate air, that is out of the question. Will I need something like that for just 1 400w HPS and MH? Or will just some fans blowing around the plants be good enough?
 

OregonMeds

Well-Known Member
No but at minimum you will need a hole in the ceiling of the grow with a fan in it to push the hot air out and into the attic or something. Or at least you'd have to have the door to the grow open every single second the light is on with a fan blowing out of it into the room. If you ever ran it with the doors closed that would be the end of your plants.

Oh wait I just noticed you said regular sized bedroom... Nevermind, the 400 will make that room warm but not too hot to kill things etc. Ybu can just have a window fan blowing or window open or suck cool air from under the house using the existing HVAC hole in the floor or whatever.
 

Little Tommy

Well-Known Member
A couple of good circulating fans should be fine. I have a 400 watt hps in a 4' x 8' x 8' oom and was able to manage the temps fine as long as I vented the room a couple times per day. Opening the door to let in some fresh air.
 

MikeTarr

Active Member
Awesome anyone else use these lighting setups? Thanks for your guys input, I feel more comfortable buying this light now. Why is a 250 wat and 400 watt HPS/MH around the same price? Just noticed that.
 

OregonMeds

Well-Known Member
Because they cost about the same to produce. Always get the biggest you can handle. You'll notice there are even 1000w lights and 600's etc pretty close to the same price also.
 

MikeTarr

Active Member
Also, a 400Watt HPS or MH, will that be a HUGE increase in electricity? My sisters BF who grows hyrdo here pays alot for electricty but he has a TON of plants. I'm only planting about 4 plants with one light..so should I expect a huge increase in price? or not much
 

BLUNTED4REAL

Well-Known Member
As far as the electricity cost im not sure theres threads on here bout that just search it, and id go with the 400 watt, i use one in a small grow box and i can manage the heat, but i use a fan for exhaust and intake, but your also using a room so you might be able to just get away with a few fans to keep the air movin
 

klmmicro

Well-Known Member
For cost, it depends on what you pay per kilowatt. I have the 400 watt HPS in your first link in a 39"x39"x78" tent and I am able to handle the heat with one 6" exhaust fan. Looked at the 250, but it is just too small once the plants get big and I figured I would end up with another light anyway.

Think of it this way, you will have the HPS running 12 on and 12 off. That is only half the day. I run mine in the "off peak" hours as I am on a tiered price per KW. It cost about $15 a month to run the light for flowering. That includes the cost of cooling and circulation fans. I have a 250 watt MH as well, and it ran me about $9 a month. The cost was too close to mess with.
 
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