Important info when purchasing LEDs: understanding PPF and PPFD

BuddyColas

Well-Known Member
I very very new to growing and leds so bare with me. I purchased the Timber diy 200w 4 cob citizen clu048 1212 kit. No frame. I currently have 2x Platinum Led P300's with really good results for me being new. I realized I should have joined RIU sooner. Definitely would like more even coverage with two plants in scrog.
Timber tells you the PPF and wall watts. I think you will be happy with them. How many sq feet are you trying to cover?
 

cdgmoney250

Well-Known Member
There is really no point in looking at charts which count only half to two thirds of the total light emitted from the fixture. Which is what those matrices do.
Knowing the light spread of different fixtures at different distances is definitely useless information....
 

Plant Lobbyist

Well-Known Member
I do like this info tho. I also would like to see more info that is more straight forward and more simple explanations like in this article.

Just get a PAR meter. HydroFarm has one for 120 bucks. It works well, just as good as a Li-Cor. It takes all the math and guesswork out and works in real time. The sooner you get one the better.
 

MasterMiller

Well-Known Member
I'm a personal grower with two 4x4 tents. I just wanted to make sure I had enough room so I went a Lil overkill on the tents. I figured a 4x4 tent really only has about 2.75 to 3 feet of actually room considering negative pressure. I'm also trying to grow perpetually.
 

MasterMiller

Well-Known Member
I would like to do some test coming from a true noob between two differnt setups so I might consider picking one up to maybe help other new growers.
 

MasterMiller

Well-Known Member
There is so much info out there and it is really hard for new guys. The learning curve, what lights, nutrients, pots, growing media, it's illegal (some places), cost, drying, curing. Shit. The list goes on and on. Head spinning really.
 

Plant Lobbyist

Well-Known Member
Possibly depending on cost

Let's work from there then.

Hydrofarm Quantum Par meter $120.00

Ok how much do you have left? Do you have a tent? Any other spare parts? Can you buy stuff used, eg. Kijjiji, Craigslist?

Grow method? 2 plant scrog? Vert? au naturale?

If you only got around 200 left, check out Cobby for 4 light engine kits and a driver.

If you have a bit more, check out the Timber Kits.

Also consider quantum boards since 2 are about 150.

For color, my preference would be 2700K low CRI and 3000K high CRI, 2 of each. You will get the benefits of >700nm (IR or FR for you cliche wonks) from both. Target for around 50w per cob, lower till you get around 700-800ppfd at the canopy. You will get 'stretch' but I find that it makes the plant more manageable for training, and anecdotally more healthy overall. Shortened flowering time can be from a few days up to a couple of weeks for lengthy strains.

Now if you can pick up a used chinese fixture cheap and are willing to upgrade it, that will save you on driver and heatsinks. Most of the drivers in the chinese fixtures will run CoBs just fine and have enough cooling to dissipate the heat. The more you can save here, the more CoBs you can get. Or a quantum board, they are an even easier replacement.

edit: Oh you already bought stuff. Ok go buy the PAR meter, you are doing fine. The meter will help you best position all of your lights in your grow space.
 

Shugglet

Well-Known Member
There is so much info out there and it is really hard for new guys. The learning curve, what lights, nutrients, pots, growing media, it's illegal (some places), cost, drying, curing. Shit. The list goes on and on. Head spinning really.
Its really only as complex as you want to make it tbh.

That being said, I spent months researching before I ever started growing. Hell, I spent over a month just researching before I dove into LED not too long ago...

But again, it doesnt have to be this complex.

FWIW, if budget isnt of concern,by all means, get the meter, but 120 could be far better spent making a better light than getting a meter if you are trying not to break the bank.
 

Plant Lobbyist

Well-Known Member
Sure, but unnecessary. But what I find funny is, Id assume you spend the money on the meter, but for what? To set your light at a height that gives you an arbitrary reading?
Also checking reflection, plant positioning, using it to track DLI, a number of things.

But the main reason I bought mine was because I wanted it. Normally when I want something I generally think everyone should have it as well.
 

Shugglet

Well-Known Member
Also checking reflection, plant positioning, using it to track DLI, a number of things.

But the main reason I bought mine was because I wanted it. Normally when I want something I generally think everyone should have it as well.
The thing is, most of that can be adequately done with a free app measuring lumens for your phone.
 

Plant Lobbyist

Well-Known Member
The thing is, most of that can be adequately done with a free app measuring lumens for your phone.
But then I am relying on some conversion factor that may or may not be anywhere near correct. I play with lots of different light sources as well.

More excuses to explain 'because I wanted one'
 

Plant Lobbyist

Well-Known Member
I like your style lol. But I dont think its a must-have for a beginner grower.

I don't know about that. A ph meter used to be essential but with organics, I don't see a use for it anymore.

I think for beginners it does explain a lot for them. Old people get it too - they are the best gardeners. Once they overcome the initial learning curve they become experts on light.

Growing knowledge is still most important. Light is only one aspect.
 
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