Dealing with high temps in Hydro

[WeedingOptions]

Hi folks,

I've upgraded my grow since last year but this new light is getting it way warmer than what I would like so I'm looking for some advice from the more experienced in dealing with it or if it is actually not a huge concern at this point. In my mind my mains problem would be the water temp rising above 80F but would like to hear your thoughts about both water and air temp.

Grow Setup
AC Infinity 36x20x62 tent
HLG 300L Rspec 270w - Running at 75%
AC Infinity Cloudline T4 205CFM - Running at 40-50%
2 x AC Infinity AXIAL S1225D 120mm (one bringing cool air from the top left, the other circulating inside close to bottom opening); up to 69 CFM each - Running at 50%
AC Infinity AXIAL 8038 80mm (bringing cool air from the bottom), 29 CFM - Running at 100%

3.5-gallon low-profile bucket
7.8 liter-per-minute (123 GPH) adjustable dual-outlet air pump
2 x 4" air stones

Temp sensor and plant are currently 27 inches from the light and with the tent 75% closed my temps stabilized around 78-79F, my room temp is 70-71F. Water temp is 78-79F as well.

If I completely close the tent temps shoot up to 83-84F which I will have to do once flowering starts. Looking back I didn't realize the tent didn't have more opening at the bottom or at least a bigger one (only one 4 inch opening).

For reference, when I completely open the tent the air temps fall to 74-75F but the water temps don't come too much below 78F.

So I'm considering a few options:

1 - Changing the layout by taking the T4 and filter outside (top) which is least desirable because I 've put a lot of effort in having everything setup in the inside with only one cable (main power) coming out from one of the sides. This would increase the total height and probably work on a better air flow distribution. Not sure if it would resolve the issue though.

2- Switching the 80mm AXIAL for another T4 which I would have the option of keeping it outside or inside on the floor. This will make the space tighter for my future plans of growing 2 plants at a time. The CFM difference could really bring more cool air inside.

3- If only the water temp could become a problem, I could add a water chiller and keep the rest as is. I still have space for it inside and could vent it's heat to the outside directly or through the T4.

This is my 3 plant btw, this one is a Magnum Auto. I heard it can get pretty big so I'm planning to top once and be aggressive with LST.

What do you guys think?

[dphipps1020]

That set up looks pretty good, very organized. There's a couple things I see that could be potentially adding to your heat. Something to keep in mind is the more electronics you have running inside the tent, the hotter it will be. Each fan will help cool, but will also put off a little bit of heat. Granted it's not usually a lot for circulation fans, but the extraction fans can produce quite a bit of heat. Also, the top of the tent is pretty cluttered and that could possibly be inhibiting the air circulation. If you can move the exhaust fan outside the tent that would probably take temps down a couple degrees. Just my suggestion.

If your tent is open, how do you have it? Meaning is it unzipped all the way like in the picture, halfway, just the top or bottom, etc? You can still leave the flap open during flower when the lights are on, I do it all the time. Just make sure to close it just before lights out. And if you want maximized cooling from the bottom, just unzip the bottom front or bottom corner and crank the extraction fan up a little bit.

You'll definitely want to get the temperature down though or you may be seeing some root problems very soon. A water chiller would be good, but they can be pricey.

[WeedingOptions]

Thanks.

Would you say that if I can lower the water temp with a chiller then the air temp shouldn't be much of a problem? I rather spend a bit more than take some stuff out of the tent, mostly for privacy issues.

I agree it's a bit cluttered, I can definitely do a better job with cable management, will work on that.

With my current fan and light setting and 40% open I get 76F air temp and 76.5-77.5F water temp, with 20-25% open it goes up to 78-79F for both temps. I also found that with 40% open my main extractor fan doesn't make much of a difference, got to run some tests with the tent closed to see the real impact.