Can’t keep VPD in range!

I didn’t know about these. I have a spider farmer 48x48x80. They have some online. I’ll look into that. Good looking out!

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If you cannot find bars for your tent… There is a another member that sells the corner pieces he 3d prints… Then for bars you use pvc or some other tubes. @CoyoteCody sells them on ebay.
Search 19mm high cfm grow tent kit… He also has 16mm and 22mm depending on the diameter of your tent poles.

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Also remember… A higher temperature air can hold more moisture.

What you truly want to avoid in late flower is dew… Which is temp and humidity close to the same… At night the temps go down after lights out… So if your moisture is up during the day because of the temps… At night you must get that moisture out before temps cool. So the cooler air does not precipitate excess moisture.

I hope that makes sense… I did just puff.

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Agreed, the numbers on the chart are accurate for the numbers provided by OP, & it is a chart generated using a +3f Leaf Temperature Offset. Entering leaf temp or leaf temp offset into a VPD calculator should end up with the same answer for leaf temp offset. You can always determine the leaf temp offset of a VPD chart by running the numbers backwards through a vpd calculator until the answers match. The chart posted by Ickey is a -2f offset chart. It’s up to the end-user to match chart offsets to their actual offsets. I guess I was wondering if you were listing your offset based on something other than the leaf offset equation, or if the app was just not working 100% yet.

Some people drought-stress their plants. Just wondering if that is what you were doing, based on your reporting the leaf temps higher than air temps. If the plants are lacking water, the leaves close up their stomatas to conserve water & the leaves start to heat up because the water stops evaporating out of the stomata & isn’t carrying the heat away.
If you water the plants & the stomata open up & start transpiring more water, I would think you would see the leaf temp offset move towards zero & negative from positive.
That’s probably the first thing I would try to suss out, is do you have a positive offset & why? It seems a little odd, but maybe you just need to water more often, or something.
Wouldn’t hurt to check calibration of your instruments as mentioned by ickey. I don’t have as much of a problem as he does with IR temp guns. Check it against an aquarium strip & if it’s off, it’s probably consistent & at least you know. Mine always checks out accurately & it’s nothing special. Also you want to be checking the RH & air temps close to the leaves you are checking. Check your instruments, then find the hottest leaf temps across the canopy, then start checking the air temp & RH close to those leaves. Then start checking everything there at different times such as before watering vs after watering, etc, until you start to see how the plant runs at different times.

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Ok. I’m 24hr light but when the ac isn’t on as much at night is when I’m seeing temps come up. I’ll have to keep an eye on it as you said I def don’t want excess moisture. And I will probably have to go through coyote because all the 4x4 I can find online are sold out. Good information. I’m gonna puff and find him on eBay. Appreciate all your help. If it wasn’t for you guys on ilgm helping I’d be screwed.

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The app is almost complete… I was having an issue with the heatmap chart coding… But working with anycharts engineering team we were able to correct that. I need to customize the legend to show the ranges of each stage per color. Also the title above with the “incorrect offset labeling” was something i through in to test my code… I am coding leaf temp now… Just completed it with Fahrenheit now just adding code to handle celcius… Then once that’s done I will be completing the stuff for if a user chooses offset instead of taking and recording actual leaf temps… Which is the way i did until i got my laser temp gun… Before i just assumed a -2–3 lower leaf temp. And chose an appropriate vpd chart. With the laser… I know my leaf temps usually are -2 from air temps.

I do use the leaf offset equation as you showed. …when coding the offset settings… The offsets will be + or - 10…however…dr bugbee has stated in a video that it really shouldn’t be more the + or - 3. He gives reasons why it would…cannot find the video at the moment so won’t quote more.

Once the offset part is done… It should be done… However, i have three more feature I am wanting to add a jacks nutes ppm calculator, and a machine learning or A. I. That will take pics and answer users question: “is my plant ready for harvest?”… Post a pic of trichomes and my hopes is to train a model for percentage of clear, cloudy, amber or combination… The last one eludes me right now… Been puffing.

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I do not chase VPD myself. Mother Nature doesnt. If they look good,grow good then I am good.

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Thanks for the shout out!

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Do you have a direct link to your store?

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I cannot post it here, but its the same picture and if you search coyotecody3d all one word on ebay you should see my profile.

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Ok just ordered. Appreciate it!

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No problem, and thank you for the support!

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I’m growing in Autopots this round. I’m looking at my app for the tent controller, it’s “night” in there on a 12/12 schedule, temp 75 degrees, 58% humidity which tells me I forgot to put the dehumidifier back in the tent. I’m within the final week (or 2 max) of my grow, and my dehum. will drop my tent to 50%.

What I did when I had an all auto run last time was run my lights on an 18/6 schedule, but broken into 3 cycles, 6/2, 6/2, 6/2. That kept things much more consistent throughout.

I have an intake fan blowing in to the bottom of my 3x3 all the time, and the exhaust and pole fan are tied into the controller and vary speed according to the parameters I’ve set.

I’ve been watching this girlie (critical mass photo) closely b/c I understand she could possible be susceptible to mold.

And on that note, upstairs to sneak the dhum into the tent!

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Mmm critical mass… def a favorite of mine. I just recently installed the ac infinity pro controller and it’s making things much easier. I can’t wait to try out the autopots. I got hard pots then turned around and got the fabrics with the socks. Not sure what to go with first but I’m sure it’ll be fun. As long as I can stay close to my vpd.

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I may end up replacing my controller with the pro, haven’t made up my mind yet. Things seemed to stay pretty well in range.

I used the cloth pots with the socks, they worked really well overall.

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Yea I originally purchased the hard pots but then saw side by side grows and decided on the fabrics. Also going to use the airdomes. I like the pro controller, kind of hard to get used to but i like that I can just set to vpd and leave it alone. Check on the phone here and there. Now ac Infinity needs to come out with all uis components. They have the humidifier and other fans ect but I want a dehumidifier that’s controlled through the system. That’ll be one less step for me.

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They’ve been adding stuff, the humidifiers are new and when I bought mine, the medium size wasn’t going to be available for a while, and the large is way too big.

I had to wait for my small one to arrive.

So I suspect dehumidifiers may come along in the future.

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Aci is doing a big reveal tomorrow. There is a rumor that it could be a dehu and 69pro+ that has 8 ports.

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I want the T7. I have a spider farmer that’s real decent but if they had one that’s a dehumidifier and uis then I’d buy both right away.

That would be awesome. Although I just got the pro the other day. Dang it. I’d still have to upgrade. I’ll be looking out for this.

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