Stupid question.. Please read though :)

Where is the best place to hav a thermomiter? Mine reads different temps all round the room.

Use 2 or 3 different ones.

I have one in my reservoir (for hydro), One mid level/ plant tops. One up top by my exhaust.

Depending on your set up you should run at least two. In pots, down by the roots but not directly on concrete. Nor should plants be directly on concrete. That way you can get an idea of root temp.

But if you only have one I think most important is by your plant tops. The heat may dissipate through the room but the vital point is the tops of your plants. The room in general could be 75 degrees but depending on room size, lights. your plants could be sitting under 85/90+ degrees.

Then again, root temp is very very important too but usually isn't an issue unless they are in pots directly on cold concrete. Which is a no no.

Not a stupid question at all! I burned my first plant not thinking it through. I agree with Scotty ^, if you're going to have one, then dangle it at the height of your plant tops, under the light. That means as the plant grows, you're raising the thermometer, too.

In my tent, there's a 20 degree difference between the tops and the bottom, especially well into flowering when the bushiness blocks light to the lower third. That's under a 400W HPS.

The most important temp is the one by the tops so that they don't burn.

I have one at the tops of the plants and one at the base

There are no stupid questions on here only stupid answers from people who shouldn't give advice about things they don't know. What's important is that your asking for advice to make those babes happy. And it's a good question indeed. Depending on what your trying to find the temp of depends on we're you will put the thermometer or tml (thermometer level). Lets say you just want room temp, don't put the tml under direct light, put it slightly off to the side away from a cooling fun or ax, never near windows or exhausts. If you want to know how hot the light is on your plants put the tml laying down along the top rim of the bucket in the center of the grow room, this will tell u temp the plants are feeling witch is generally hotter than the room temp. Root temps can be found by putting a tml in the potting soil it's self, however if you burry the tml to low in the soil the top of the tml can get heated by the light and throw off the root temp, so get a little cozie drink umbrella and keep that sucker in the shade and u will read proper root temps.

Hope this helps

Chears guys.

kryptoniteglo said:

Not a stupid question at all! I burned my first plant not thinking it through. I agree with Scotty ^, if you're going to have one, then dangle it at the height of your plant tops, under the light. That means as the plant grows, you're raising the thermometer, too.

In my tent, there's a 20 degree difference between the tops and the bottom, especially well into flowering when the bushiness blocks light to the lower third. That's under a 400W HPS.

The most important temp is the one by the tops so that they don't burn.

Click to expand...

I had this issue as well. Major temp difference from the bottom (where cool air was being pulled in) to the top where the heat from the light kept things warm. I got a stronger CFM fan mounted on the top of my box, pulling that cool air stronger and it leveled out my temps. I have about a 5 degree difference from the tops to the bottom now (current strain is 5 feet tall counting planter).

I use 2 different temp/RH gauges in my room.

One at canopy level out of direct light and another at pot level.

My hi's and lo's rarely exceed 18C-23C.

But I use a temperature sensored fan speed controller.

I'm capable of controlling between 16C-35C depending upon what I want to do.




J

I dont hav to much control over my temps there between 18-28c :/