Temperature issues clarified.

[raoulduke2.0]

Most of the threads I've read stated that he ambient temperature in a grow space should be between 70 and 80 degrees. I have a grow box in a closet and the temp in the closet is never over 80 but the temp inside the grow box is in the upper 80's.
If my plants are still growing strong in this temp, will I have problems later?

 

[HMAN]

http://www.marijuanapassion.com/forumWOW/Full-Marijuana-Growing-Guide.html#TEMPERATURE

 

[massproducer]

the temps outside of the box are not the temps that you want to measure, you need to worry about the temps inside the box. What type of light are you using? What type of ventilation are you using?

The high 80's is definiatly starting to get into the danger zones, you need to extract the air away from your closet and grow box

 

[Aurora_Indicas_Dad]

they may grow under these conditions,but that doesnt mean theyre not stressed by the heat.im fighting heat issues also,its part of the reason why i've delayed my main grow this long.summer and indoor growing dont go together well,unless you have your ventilation/heat under control.im buying a small window a.c. myself.

 

[kailiwela44]

I have a very similar grow as you, box in a closet. The temps inside my box peaks 90, but not too long--mostly mid and upper 80's.
I do have one plant out of three, grown in these conditions, that is a female. I try to balance the heat by using co2--yeast, sugar, h20--from others advice it can be used to about 95degrees.
Try to get a fan blowing air on the plants or lights and if possible leave your closet open. If can, do not let the cooler air mix with the hot air--cold air falls and hot air rises. If your closet is cluttered it restrict air flow. My temps lowered once i organized the crapola in there.
It would be a good investment to use B/W poly to block the light which may be coming from your box. This will also help keep the closet dark during flowering.
If your tips on the leaves curl up toward the light, that is a definite sign of heat stress. Plants may also hermie.

good luck,
kailiwela44

 

[raoulduke2.0]

I found that the closet in my garage that is air conditioned. The ceiling is also high so I think that cool air will fill the part of the room that the box sits in. The light escape aspect is one I hadn't until now seriously considered. I have been reluctant because I wanted the box to ventilate. It's hard to fabricate a vent that doesn't let light escape.

Wouldn't the circulating air make the CO2 impotent. I have tried the vinegar sodium bicarbonate method but I felt like was wasting my time. I have a packet of champagne yeast and i'd like to use it but I feel like if the air is circulating well that it will be wasted. If you want big lights you must have air circulation. If you want good C02 uptake you've got to have good lights. So how do you get big lights, circulation, and C02?

 

[King Bud]

It's hard to fabricate a vent that doesn't let light escape.

Make a 90 degree turn with your ducting. If this is not enough, make it 180 degrees (like a C). If this is still not enough, make an S.

Temps can drift higher, when using CO2. Infact, I think plants absorb more light in higher heat. I think I've read that 90f is 'optimal' when using high CO2 levels.

So how do you get big lights, circulation, and CO2?

Well, the only reason you want circulation, is to get a fresh supply of CO2.

Say you're adding CO2 with a tank.. you would set it up either on a timer system(ex: leave valve open for ___ minutes), or on a fancy electronic monitoring system (ex: maintain ___ ppm of CO2 during these hours). CO2 is usually turned off during the nights, when flowering, so as to not waste CO2.

Temperature is controlled through a different system. When you can manage with the heat, set up a thermostat to your fan/carbon, so that air is only exhausted when it gets too hot (to waste least amount of CO2). For larger rooms, sometimes an A/C unit is needed. Dehumidifiers may also be needed. For these, separate controls can be bought, or you can get the fancy all-in-one units.

I think the only way to know if you need A/C or dehumidifier or not is to try it out. Ambient temperatures, growing style, and a whole slew of things can make heat/humidity very different from growroom to growroom.

Air cooled hoods are also a popular way of dealing with the heat from high wattage lamps, without affecting the CO2 system. No extra carbon filter is needed, since the air is pulled from outside the growroom, through the hood (which is sealed with glass), then out the growroom again.

 

[Driphuse]

I read everywhere that the tempertures should be 24 to 28 celsius (75 to 83 Fahrenheit) but it also depends on wether the grow is soil or hydro.

I grow mine on 77 to 90 (it varies) and they're doing just fine

Fahrenheit to Celsius Converter: http://www.wbuf.noaa.gov/tempfc.htm