Hello all!
Ok, so my setup is as follows: i have 5 plants (chiesel) about 4 weeks into flowering. For the veg and the first 2 or 3 weeks of flower i used a 400w MH and HPS respectively. Then i got a 600w system and hooked that up. Grow space is a 1.2m x1.2m x1.8 (or 2m, cant remember lol). Only got a 100 M^3/hr extraction fan, which i know isnt enough for my setup - BUT, with lights on (at night, in winter in ireland), a passive intake duct from an open window with a fan (not inline) right at the end of the ducting (inside the tent) bringing in enough cool air to keep the temps in check, and a dehumidifier to keep the temps slightly up and humidity at 60% at lights off, the temperature range is acceptable with the 600. Hitting about 28-29 C at the canopy (82-84 F) at lights on, (and maybe 25-28 if its windy out) and dropping to about 18-20 C (64-68 F) in the dark.
Now, i hooked up the 400 as well with the MH bulb, for the triple effect of more lumens, more points of light, and more varied spectrum. The temps with both lights on hit about 32 C, slightly less if i leave the tent door open or its windy. I know this is a tad high, but i have the fan blowing cold air from the intake duct and an oscillating fan at the other side of the tent so plenty of air movement.
My quandry is this:
Will the higher temperatures reduce yield more than the extra light would otherwise add to yield?
Is it best to keep it at the lower temp with just the 600? or will the extra 400 give a better yield even though temps are slightly too high? or will the high temps drop yield even though there is more light? There doesnt seem to be any sign of heat stress on the leaves btw.
If it turns out that the higher temps are detrimental enough to reduce yield with the 400 on, what i'l probably do is only have the 400 on for the first few hours of the light cycle and then turn it off, and keep the tent door open! unfortunately i cant afford a better extraction fan at the moment.
I dont want to damage my yield be being greedy with my lighting! any you guys have experience of this type of situation or similar? a lot of you guys are pretty clued up about growing and hopefully you can tell me definitively whether i should stop being a greedy ass, looking for a bigger yield with more light, and just keep the 600 on (with maybe the 400 for a couple hours) OR whether the extra light will overcome any ill effects from the temps?
Thanks in advance!!
Peace.
C
Ok, so my setup is as follows: i have 5 plants (chiesel) about 4 weeks into flowering. For the veg and the first 2 or 3 weeks of flower i used a 400w MH and HPS respectively. Then i got a 600w system and hooked that up. Grow space is a 1.2m x1.2m x1.8 (or 2m, cant remember lol). Only got a 100 M^3/hr extraction fan, which i know isnt enough for my setup - BUT, with lights on (at night, in winter in ireland), a passive intake duct from an open window with a fan (not inline) right at the end of the ducting (inside the tent) bringing in enough cool air to keep the temps in check, and a dehumidifier to keep the temps slightly up and humidity at 60% at lights off, the temperature range is acceptable with the 600. Hitting about 28-29 C at the canopy (82-84 F) at lights on, (and maybe 25-28 if its windy out) and dropping to about 18-20 C (64-68 F) in the dark.
Now, i hooked up the 400 as well with the MH bulb, for the triple effect of more lumens, more points of light, and more varied spectrum. The temps with both lights on hit about 32 C, slightly less if i leave the tent door open or its windy. I know this is a tad high, but i have the fan blowing cold air from the intake duct and an oscillating fan at the other side of the tent so plenty of air movement.
My quandry is this:
Will the higher temperatures reduce yield more than the extra light would otherwise add to yield?
Is it best to keep it at the lower temp with just the 600? or will the extra 400 give a better yield even though temps are slightly too high? or will the high temps drop yield even though there is more light? There doesnt seem to be any sign of heat stress on the leaves btw.
If it turns out that the higher temps are detrimental enough to reduce yield with the 400 on, what i'l probably do is only have the 400 on for the first few hours of the light cycle and then turn it off, and keep the tent door open! unfortunately i cant afford a better extraction fan at the moment.
I dont want to damage my yield be being greedy with my lighting! any you guys have experience of this type of situation or similar? a lot of you guys are pretty clued up about growing and hopefully you can tell me definitively whether i should stop being a greedy ass, looking for a bigger yield with more light, and just keep the 600 on (with maybe the 400 for a couple hours) OR whether the extra light will overcome any ill effects from the temps?
Thanks in advance!!
Peace.
C
