375w cfl vs 400w hps

jaycuffee21

jaycuffee21

Well-Known Member
i have a little dilemma my plants have been on there 36hr darkness b4 i throw them in flower im currently running cfls 375 watts mix(23,26,25) and my temps stay around 78 with lights on and 73 ish when there off, now this is my second grow 1st grow was okay but got airy buds(damn cfls) this time i wanna upgrade i was either debating a 250w hps or 400w hps, i got perfect ventilation 2 exhaust,1 passive intake and 1 fan blowing on my 5 plants in 6 and a half sq feet, but will heat be an issue , any feeback welcome (keep in mind i have 375w cfl right now) would you go with a 250 or 400?:leaf:
 
bigv1976

bigv1976

Well-Known Member
You should be fine with a 250 and it would still be a huge upgrade but if you think you can get the heat out the 400 is perfect for 6 1/2 sq. feet.
 
snowwhitebudman

snowwhitebudman

Active Member
well i switched from 305 watt cfls to a 250 watt hps and my baby is doing so much better. i had 10 light total 4 23 watt, 4 27 watt, 1 65watt and 1 40 watt
 
bbarnes

bbarnes

Member
If you're running hot with cfl's, you'll cook them with hps. even a 250. Your intake and exhaust sizes should at least be equal, if not bigger on the intake side. I got 450 watts of cfl's in a small unventilated cloning chamber that runs at 78-80, and a 4 x larger area with dual 4" fans up hig, dual 4" intake holes, a 250 hps and I still stay at 76-78 at canopy top. intake air is around 70-72.
 
bigv1976

bigv1976

Well-Known Member
Well he clearly stated his temp was 78 so why would you answer about if he's running hot? He's not!!
 
bbarnes

bbarnes

Member
I think that 78 is on the upper limit of flowering temp. I also prefer lights off temps in the mid-upper 60's. YMMV

edit: I guess it's unclear on if the grow room is 78 or the top of the canopy. My canopy top is about 4-5 deg warmer than the grow room temp. Higher temps not so bad during veg, but I think it's better to drop it a bit during flower.
 
Xan2

Xan2

Well-Known Member
bbarnes said:
If you're running hot with cfl's, you'll cook them with hps. even a 250. Your intake and exhaust sizes should at least be equal, if not bigger on the intake side. I got 450 watts of cfl's in a small unventilated cloning chamber that runs at 78-80, and a 4 x larger area with dual 4" fans up hig, dual 4" intake holes, a 250 hps and I still stay at 76-78 at canopy top. intake air is around 70-72.
Click to expand...
You don't want a bigger intake than exhaust, this creates a positive pressure in the room and even with a proper filter the smell will somehow leaks.

bbarnes said:
I think that 78 is on the upper limit of flowering temp. I also prefer lights off temps in the mid-upper 60's.
Click to expand...
80F is the ideal temperature for the plant and the rootzone.
 
jaycuffee21

jaycuffee21

Well-Known Member
yeah i think the 250 would produce some decent yields , or would i be betta off jus stickin with the 375 watt mixed cfls( i went to my local dispensary and talked to a grower and according to him considering how much space i have to work with im better off with cfl and reflectors)????!???
 
DankShasta

DankShasta

Active Member
well two things from this thread....

1) 78 degrees Fahrenhiet is about the upper limit for flowering, without CO2 anyway, so if your at 78 with flouros you'll prolly need to do alittle better with a 250hps, and you're really going to have to figure something out if you go to a 400 hps.

2) it's true you need slightly more exhaust than intake to control odors, but passive intakes you just want them BIG as HELL.

that is all..............


p.s. why are a your flouros so hot? 78 is not bad at all, but it sounds like you have a decent ventilation system for your space?
 
bbarnes

bbarnes

Member
Xan2 said:
You don't want a bigger intake than exhaust, this creates a positive pressure in the room and even with a proper filter the smell will somehow leaks.
Click to expand...
He said passive intakes, so the fans are on the exhaust for the very reason you mention (no positive pressure). In this case you DO want your intakes greater than or equal to the exhaust.


Jay, sorry about your post turning into a pissing contest, preferably everyone will give their opinion to you and you will have make a determination on what works for you.
 
TheDude0007

TheDude0007

Active Member
:-)That's not alot and I would agree bigv1976. It is far from any limit. :-)

As long as your plant does not get heat of more than 35 degrees celcius which is 95 degrees fahrenheit you are fine. It may sound very hot, but as long as your leaves are 30 cm away with a fan blowing on the plant, you will be fine. Any hotter you have a problem. :-) In my opinion anyway. :-) 78 degrees Fahrenheit = 25.5555556 degrees Celsius



\\
 
jaycuffee21

jaycuffee21

Well-Known Member
yea my plants are responding fine i just replaced my old exhaust pc fans and put better 1s in along with adding 2 27w 65k cfls for mixed specturm now putting me at 429 actual awattage for my lil 6/12 sq ft box, plants have been on 12/12 three days now i can definitely see the stretching and tiny white pistils forming on 4/5 plants in there i will try and have pics up later trying ta find my usb cord,(its hard to locate shyt when ur smokn ak and pressed kief!!!lol
 
pinkjackyle

pinkjackyle

Well-Known Member
hot temps make airy budz , if hps is not gonna happen check out some t5'ho's i swear theyre cooler and they make grow bulbs for them or can use the cheaper ones
 
jaycuffee21

jaycuffee21

Well-Known Member
yea jus got bac from loacl wally world they chargin 8 bucks for a 42w so i picked up three of them replacing my 23 watters puttin me at 413 actual watts (26,27,42) both daylight and soft white also i picked a piece of sheet metal for a reflector, i discovered my purple urkle attacked by these nats and wondered why, passive intake hole was inviting them so i put a desk fan as my intake, i got a pretty good feeling bout this grow will post pics, soon as i find that damn usb cord
 
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