Humidity and Temp Tips.

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Mar 31, 2011
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Hi everybody, I have just set up my tent 80x80x160cm in my basement and for the last week have been running it to test with a 250wattcfl inside , and it's been running 12/12 , when i checked max humidity this morning it had been at 94%max and 66%min,it averages at 70% with light on. Temp is averaging 59f with light off and 69f with light on, i have another light , a hps 200watt with reflector i plan on using for flowering,would this increase my temp a fair amount?? does anyone in the community think plants could be raised in that environment???, i'm worried about mould on my beautiful plants. any tips for keeping away the dreaded mould in general.

Ty all

yea that humidity (RH) is way to high. it should be around 50-60%. and your temp should stay around 72-78F. and yes more lights you have would help the temp go up, and what is your ventilation set up? you really need to exhaust all the old stale air out and push new air in. Good luck bro and happy growing
thats it^

you need to pull out the humid air and replace it with dry air. That another light will raise temp which in turn lowers relative humidity.
ty for reply buddy , i thought i might be able to get away with it but you are right there is no way its going to work, think i'll invest in a small dehumidifier. any way i can keep humidity in tent without doing much outside??

@ Kushman , Ty for your input, i think having both my cfl's on and then hps when flowering should raise temp quite a bit , well i'm hoping ...:)

Much appreciated guys....

Peace all
i never said i but i have no fan on my tent yet so that will defo help after hearing what you both said...ty
you need an exhaust fan. and a dehumidifier makes a lot of heat and draws as much as 1000watts (mine draws 940watts!)

easier cheaper and smipler to exhaust humidity instead of condense and collect it
How many lumens do your lights put out? This is info you need to figure how much space the bulb will adequately light. A 250W CFL is not going to be nearly enough light for that space, which is going to require about 35,000 lumens for flowering. I have never heard of a 200W HPS--are you sure it is a HPS? Again, how many lumens? You need to get both the temps and the RH down and get substantially more light in there.

You absolutely need ventilation--exhaust. Plants need a continual supply of fresh air all the time the lights are on. A 4" centrifuge type fan (Vortex, Eclipse, Can, etc) should be fine for your space.
whats the best cost effective humidity, temp meter... opinions?
an analogue thermometer and hygrometer would likely be the cheapest option.

There's an old saying in the drag racing fraternities; Speed costs money, how fast do you want to go.

If it were me I'd shell out a little more for a digital combo meter which would cost around $20.

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