New to the forum but not to growing

I think I’ll go with what he said …:arrow_up:


Thank you @new2-420 . I appreciate it. Some more coming in a day or so. Just another piece of puzzle. I keep finding them lol. Come on back and hell, I have ideas for an economizer too. Somebody stop me.:v:

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@PhotoFinisH we’re walking that path but you sir…I can’t see where you are up there ahead of me. Let me catch up a little. I just leveled the canopy a bit, they weren’t doing it on their own. And thanks to you, I have yet another app on my phone…:rofl:…just kidding with you. I’m actually thrilled it’s looking like i don’t have to buy another meter. Something we all have, can work…along with an app, as a ppfd meter. I have an android, s22+ to be exact, but even the cool-aid drinking iphone snobs lol can get in on this. :joy: It’s cool my almost 80 year old mom has 1 too.:grin:

Anyway…I need to “calibrate” my phones ALS within the app for more accuracy. I went ahead and tried it out, gotta say…it looks very promising. With the options you can select, I chose 4k temperature with, 10% I think ir boost. You can’t select %, you either have it or not. But once all options and calibration are complete, there are also tips for better readings :thinking: iirc. The accuracy is supposed to be on par with a $500 sensor. Alternatively you can buy a cheap Bluetooth sensor, use it with the app and you’re good.

Other than that, I’m still learning what ppf, ppfd are lol. I get it now and I need to figure this all out before flower preferably.

As far as previous knowledge on this goes, I got nothing. I wired up a ballast, ordered some seeds and did a lot of reading on overgrow and icmag forums. Forums are awesome, don’t get me wrong, but I found difficulty finding definitive answers to various topics. I came out of it knowing how to clone, when to harvest and Miracle-Gro is not what you want for fertilizer :joy:
Don’t pee on your plants either :rofl::rofl:

I want to say leaf surface temperature has to do with the amount of ir light your fixture produces. I know the bloom plus I bought has ir leds for this. My initial statement that this light falls into the -1 to -2 lst category may not be as accurate as I thought. I still need to calibrate, set my proper distance and intensity then go from there. I think I’ll have some good data though.

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@Coonass :joy: I would too. Like I said he’s a little further up the path.

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I can definitely feel the difference in radiant heat between my old 270w HID bulb & my new ~220w - 250w LEDs, & my LEDs have some far red too. HIDs put out a lot more of it. This loss of leaf surface temp from lack of radiant heat seems to be a bigger problem with blurple lights. A full spectrum LED even without far red should put out more radiant heat than a comparable ‘blurple’. But still less than a comparable HID.

I don’t know too much about setting up the phone-based light meters, but there are people who do. I have a cheap bluetooth meter, but it gives out similar numbers for my light as compared to third-party testers on the same light at same testing distances, seems to be good enough. (Although it is not an EPAR meter, so if my light has some IR or UV shining out of it, I know my meter is not showing me those photons & I can just add a little in my head.)

I use this chart to decide around how much DLI I want. This chart is for photoperiod plants. There is a different chart for auto plants which you would want to find if you are growing autos. The color code is screwed up, the numbers above the other numbers are for if you are using CO2.

Then I use a DLI calculator over at the waveform lighting website
to enter ‘guesstimate’ PPFD numbers until I get the DLI number that I want. You can use this same DLI calculator for photo or auto plants. Don’t forget to put in the correct hours for how long your light will be running for one day. Then I adjust my light until my meter reads the same PPFD number from the DLI calculator.

@PhotoFinisH I don’t know anything about burple lights except to stay away and my brother has 2 I think :rofl:. Exactly though, hid lighting produces a ton of heat compared to latest leds. I don’t know all the benefits of ir spectrum, but I’m sure warming things up a little is at least part of the reason for adding them.

If you have a smartphone, the app I’m talking about is what you want. Unless there’s better, I’m giving it a try. Smartphones have an ambient light sensor, als, typically somewhere along the top of the screen. Used for dimming the screen or front camera light detection. Download and install app from google play or wherever you go for apps. It tells you everything to do. If it turns out your phones sensor isn’t up to snuff, buy a $40 BT sensor which you have it sounds like.

I haven’t messed with except initially trying it out, but it works as a dli meter as well. You just enter the hours of light. :boom: done!

While this is a part of the grow, we’ll see where it leads, but not turn it into a ppfd thread. Or a plug for the meter app lol. I am liking it though. Just seeing it respond appropriately to distance from a light source, as I moved my phone from plant to plant, and the light source options you can select, it’s a useful tool no doubt. It’s built for growers by growers. I’ll contribute, it’s worth something and some time has been put into it. Search apps for ppfd meter.

Helps to take the guess-work out. Have you started checking leaf temps & seeing where your leaf VPDs are?

I give up

Starting over. New title for journal, everything.

Beefy’s adventure into the unknown…

Chapter 1 - 1st time using led grow lights

Chapter 700 - VPD


I mean it though…after this grow im starting over lol. This has been unexpectedly overwhelming. I set out to learn about IDEAL growing conditions and just be more efficient with the grow. I didn’t expect the learning curve with leds. I didn’t know what I was getting into with vpd. I took on too much at once. Time to get back to the basics after nearly killing the plants. No pictures of that, but I started making adjustments based on the vpd chart that I thought was right for my light. Checked on them at the end of the day and they looked like they had given up on life. Limp as could be. I was trying to put an end to the stretching. Plenty of that to come. They survived thankfully and here we are at day 35 veg.


I wasn’t going to top them. Wanted to see what they did on their own. Including the container, GSC #3 was a 22" bean pole. I ended up topping all of them. Even Runtz #4.

I’ve been struggling to dial everything in. Mostly humidity. I would like to get everything stable before flower, which, I’d like to be in by the end of the month. It’s only 2 weeks since transplant but I’m thinking about final transplant the end of this week or next. They were watered with 1/2 strength nutrients yesterday. Don’t want to see any deficiencies like what started before last transplant. I guess I could measure some runoff to get an idea.

Not saying that your VPD is a problem yet, but reading your post & I feel that you went through the same thing that I did. VPD charts are misleading if the leaf temp offset is wrong. That’s why I stopped using them & went to the calculator.
Use your IR gun, find the hottest leaves on the tops & also get an idea of the leaf temps across the top of the canopy, & record the results. Measure your air temp & RH right around the area with the hottest leaves. Then you can start to see where your Leaf VPD is.
I usually use the calculator at the dimlux website because I can run a bunch of numbers through it quickly & see the different potential Leaf VPD results quickly. The Leaf VPD tells you how fast the leaf is transpiring. Use a guide & pick a Leaf VPD target range based on what stage the plant is in. If you let the Leaf VPD number be your target, you can tune the leaf temp, air temp, &/or RH to reach it.

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@PhotoFinisH that was the plan. Thought my lst was -2. It’s more like +1-2°f. Air temperature, I have a good reading on that I believe. Doesn’t seem to matter where I take it as long as it is shielded from the ir. I’m having trouble opening the tent to do anything that takes much time. Throws my readings out of wack for the rest of the day. My Humidity is high right now to give me some room for error. I’ve been using a vpd calculator and +1-2 lst. I just don’t have the time to do everything I want.

I did some more ductwork. Still not exhausting anything. I don’t know🤷‍♂️…making it up as I go.

I think I want that tee moved and I need more backdraft dampers. Maybe just 1.

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Your girks r looking good

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The AC-Infinity Cloudline Controller #67 drove me crazy trying to chase VPD.
LSS, temp and humidity of tent are the starting point. Then use the laser gun for measuring leaf temp.
formulat for VPD = Leaf temp MINUS air temp.
Note, air temp in my tent is 3-dimensional and any movement with in hanges any one othe the 4 temp devices. If you back hand does not burn at leaf canopy, and leaf measure les than ambient, then VPD gets smaller.

Again, 10,000 years cannibus cultivation and nobody knew…
If you don’t burn them and RH is good then mybe life is good

Good growing to you

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