Trying to keep temp/humidity/vpd stabile

[shooter64738]

So this is first grow in an actual tent and I'm having a really hard time with temp and humidity.

Running 2 vivosun 4x4 650 lights in a 4x8 tent. It's all setup on a grow hub control, and maybe I'm just watching too much.

With lights on at 80% my temps start at 75°f and then steadily climb to 88°f. The exhaust blower comes on and the temp drops to about 85, and then back up to 88. When the light goes off temps come back down to 73°.

My humidifier is running through almost a gallon of water per day trying to keep the vpd below 1.5 but it's a struggle. The Lung room is perfect at 73°/60%.

I can set the exhaust to run constant when the light is on and keep the temps in check, but am I doing something wrong here? My 4x4 running a small spider farmer light sets at 74° all day long, and the exhaust just kicks on once in a while for air exchange. Is there a specific way to vent these tents I'm missing? I have the bottom screened vents open. It's cool out thos time of year and I can pipe in outside air If I need too.

My plants are growing really slow and look stressed. I'm also growing in coco for the first time, but they did really well in the 4x4 so I think its just wild temps causing me issues.

Any thought on temps? Maybe too much light? It's the recommended light for a 4x8 from vivosun.

 

[shooter64738]

Well I may have solved my own problem.

My exhaust fan is too small (4") vivosun recommends an 8" with those lights so I added my spare exhaust fan and its dropped down to 76°. I should have thought of this a day or 2 ago!

 

[LoveGrowingIt]

Getting everything dialed-in can be quite a challenge, even with a controller. It can take a lot of tweaking.

 

[shooter64738]

Getting everything dialed-in can be quite a challenge, even with a controller. It can take a lot of tweaking.

For sure! I switched to indoor and automated because I can't do all the physical stuff I could before. But now that I can keep the temp in mid 70s I think plants will be much happier.

Now to learn as much about coco and nutrients as I can!

 

[voltage]

You are running 2 650 watt leds in a 4x8 tent?

 

[shooter64738]

You are running 2 650 watt leds in a 4x8 tent?

Yes. Been running smaller spider farmer sf1000 lights in a 4x4 to get seeds started, then move outside in spring. Grew 2 plants with them indoor last winter (make shift tent) and they did ok, but not fantastic.

So I got the bigger lights that are supposed to be good for a 4x4 to flower 4 plants. Then got one for each side of the 4x8. Currently running at 60% intensity. I won't be growing outside anymore so I needed a setup to go from seed to finished.

Ordered an 8" exhaust to put on the tent to keep temps down better. It's currently holding at 75.3°f running a pair of 4" blowers.