Need help with PPFD

Hi guys, so basically im trying to maximize my grow indoors. I notice the ppfd for seedling and veg is around 200-600 ppfd. But when I go outside the ppfd is 1000+. Should I try to maximize the ppfd to 1000 or should I just keep it in the range of 200-600? Thanks.

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I just use a phone app (not as accurate but good enough).

Led vs sunlight is the difference in ppfd, I imagine but I am nooooo expert here.

Led, safe to say seedlings around 300-ish area I’ve seen great results, talking first couple weeks of life. Not trying to melt them from heat. Hope that helps!

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300-600-900

Give or take.

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i usually get bleaching at over 600ppfd, per the phone app, even in flower…i wonder why?

Start at 200 - 300 and watch your seedlings. If they start to stretch, turn it up a bit. Continue until they are not stretching anymore and go from there. The plants will tell you what you are asking your meter to tell you. :v:

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Which app are you using?

photone app. i am not getting bad yields or anything. i hit 50g per sqft last round

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I’m not an app expert but that’s the one I use. I paid the $8 for the LED option and tested it to manufacturers specs and it was within acceptable tolerance.

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Lol, you kids and your gizmos. I still say listen to your plants. Everyone wants to use some kind of electronics but I wonder what then happens when said electronics are not available for one reason or another.

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yes, your observation is correct. if a seedling can survive and thrive outside on 1000+ppfd then it can survive and thrive inside on full blast (supposing you have your environment within healthy parameters) .

I could’ve just followed manufacturers directions but I’m a belt and suspenders kind of guy.

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I get it, I didn’t trust phone apps or, more importantly, phone sensors, so I bought a quantum par meter, I just rarely use it because my plants provide enough information.

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I tested the app against numbers that I trust and it’s bang on.

But I was also dialing in a new light and needed some info to feel comfortable with it.

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For me I tried the same app on 2 different phones and got very different readings.

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It took a little troubleshooting but once I put the paper filter on it was smooth sailing. Again, against numbers I trust if I probably wouldn’t have bothered.

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Yea, but for free you could just watch what the plant is doing and adjust. Once you do that a ppfd reading is irrelevant.
I have an issue where I like gizmos and to mess with stuff. Most of it doesn’t get used much anymore.

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Perhaps but $8 worth of peace of mind is worth it. And it’s a fun toy to play with. My pH pen that I don’t use was WAY more expensive :joy:

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I get it man, I love toys too. Drives my wife nuts.
I also have a ph pen, just sitting somewhere, sad and alone.

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How well do the drops work when you’re feeding with nutes that cloud the water? Do you just dry amend and top dress regular h20? Asking, as I use the drops too and always end up with the ph meter when feeding.

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Yes cloudy water complicates the drops.

My ferts turn the water brown so you kind of need to do the correction for it in your head. The drops are more for range than precision anyway so it’s not a super hard equation.

That’s how I do it anyway.