Rahz' notes and observations

[Evil-Mobo]

By optimal I think you mean optimal growth rate, and what you're saying is true but the chart also suggests 75% growth rate at 50% of optimal light intensity, so it makes sense to limit the veg intensity to around 700 or so until we're all getting fusion powered electricity at pennies on the dollar, and honestly even a PPFD of 450-500 is going to provide a fantastic veg if all other parameters are keeping the plant healthy. As far as yield some suggest it's close to linear but my own efforts haven't proven that out yet. Keep in mind I just recently upgraded my equipment and prior to that never used over 800 PPFD in flower. So far, jumping from 800 to 1250 has resulted in an increase from 58-60 to 72 g/sqft. I think I can do better than 72 g/sqft but for the curve to be linear I would need to pull over 90 g/sqft. I know it's been done before but probably beyond my skill level even with these nice lights. And you know, getting 60 g/sqft from a light that isn't quite hitting 800 PPFD ain't too bad.

I've always argued that it's not the most practical thing to grow with +1000 PPFD. Better to use same wattage with more space. But efficiency goes up and price goes down, and I was curious. I'm doing it for science

So my 3x3's were running a higher watt per sq ft than my 4x8 is. I got in the garden tonight and switched some lights around. We will see what happens. I now have (2) 3K 1812's on a meanwell 1050 driver each one and (2) 6500K 1212's on a meanwell 1400mah driver in each 3x3. I took one cob of each color temp and moved it elsewhere for a new nursery space. To my eye the mixed spectrum looks a lot like the 3500 K does on it's own, but a little more "realistic" like being outside not sure if that makes sense.

I'm pulling 228 watts at the wall on the kil o watt meter for just the 4 COB's in each 3x3............let's see how the plants respond. Like you said this is not a lab controlled test but there is merit (i think so ) to the things we are finding with the less is more theory............



Ok I want someone's help here who is better at software stuff than I am. How could I create a chart/graph where I can over lay the citizen spectrums of my 6500K/3500K/3000K over the spectrum of the new Hortilux LED lamp? I would be really curious to see how this compares.........

Thanks guys I am enjoying this thread and the info back and forth


@hybridway2 Tagging you because I think some feedback from you would be killer as well since you have grown a fair amount under HID & LED as well............

And you have the strip lights going forgot the brand but way out of my price range so I haven't been able to get my hands on them

 

[Evil-Mobo]

@Evil-Mobo we had done a couple different ways, the biggest difference was a 4000k/70cri fixture, then the 3500k/80cri, and the 3000k/90cri over a 4'x8' tray. After 2 or 3 weeks, it looked like a staircase of plants about 6" tall every color change, but the 4000k lack canopy density. This was all to long ago for me to remember what wattages we were using, since we changed it up everytime and I only made it there 2 or 3 times per test.

Oh, the 2 DE were on high, and we did almost half the wattage, 20% less, and about the same, but again I was so busy at this time and my friend was gone most of that time and none of these runs were his better runs (lazy helper let problems get out of hand). We weren't running the COBs for efficiency either. It was 12 CLU058 3618 over the 4'x8' tray on some 20 pound 600w heatsinks

Yeah it was a while back I wasn't expecting you to know off the top of your head. You're one of the handful of guys on here I have seen try so many different things with his grows besides me lol..........there's a few of us nut cases like that but not many. And you're one of few guys I've seen or know that has enough time with the HID's and the COB's so you get what I'm talking about better when I log notes and pics about comparisons whether side by side or not. I appreciate the reply and the input. I think we can get some interesting info back and forth in here especially if some more people can chime in with honest feedback not biased by ulterior motives...............

 

[BuddyColas]

By optimal I think you mean optimal growth rate, and what you're saying is true but the chart also suggests 75% growth rate at 50% of optimal light intensity, so it makes sense to limit the veg intensity to around 700 or so until we're all getting fusion powered electricity at pennies on the dollar, and honestly even a PPFD of 450-500 is going to provide a fantastic veg if all other parameters are keeping the plant healthy. As far as yield some suggest it's close to linear but my own efforts haven't proven that out yet. Keep in mind I just recently upgraded my equipment and prior to that never used over 800 PPFD in flower. So far, jumping from 800 to 1250 has resulted in an increase from 58-60 to 72 g/sqft. I think I can do better than 72 g/sqft but for the curve to be linear I would need to pull over 90 g/sqft. I know it's been done before but probably beyond my skill level even with these nice lights. And you know, getting 60 g/sqft from a light that isn't quite hitting 800 PPFD ain't too bad.

I've always argued that it's not the most practical thing to grow with +1000 PPFD. Better to use same wattage with more space. But efficiency goes up and price goes down, and I was curious. I'm doing it for science

Great to see you posting your notes from your garden.

Please clarify then "4/2g gallon through to week 8" from your post above.

And over 2 ounces a square foot from less than 800 umols and no CO2 is quite good in my opinion. Keep it up.

My res gets in the low 70s. But with Hydroguard I have had no issues.

 

[Evil-Mobo]

Great to see you posting your notes from your garden.

Please clarify then "4/2g gallon through to week 8" from your post above.

And over 2 ounces a square foot from less than 800 umols and no CO2 is quite good in my opinion. Keep it up.

My res gets in the low 70s. But with Hydroguard I have had no issues.

Hydro guard is such a great product

 

[ttystikk]

Also, I never run ppm over 1000. I do want to experiment one day, but you don't need outrageous TDS to pull good yield. In the past I kinda winged it based on recommendations, but after digging a bit deeper I've got to the point where I measure out nutrients by elemental ppms. General rule of thumb is 100-150 ppm Nitrogen for best vegetative growth. I've been shooting for 100 over the last couple grows but would like to play with bumping up closer to 150 during veg, could be especially helpful for getting bulk in the first two weeks if I'm going to shorten my veg period and maintain root ball size going into flower... but I wouldn't be surprised if going from 100 to 150 didn't produce a lot of difference.

As far as the P and K, range for P seems to be 20-100 and for K 150-250. In these hydro systems I've been keeping P at around 20 using CocosAB formula and then switching to 50 ppm at the start of week 3. I've been doing this because P (typically cited at +70 ppm) inhibits various beneficial microbes and I had some root rot issues and the rot doesn't seem to care what the P levels are. Now that I've got the situation under control I'm getting less paranoid and thinking 50 ppm P will be fine to start with, and again if I want a 2 week veg it makes sense to kick the P up ASAP.

I know less about potential min/max of K. I base my 250 ppm figure on adjusting nitrogen of various brands of vegetable fertilizer to 100 ppm and see what the K comes out to. If I bump the N up to 150 that can put the K as high as 375... but for perspective these are fertilizers intended for soil so it's going to get watered down to some degree as soon as it's applied. Analyzing hydro specific nutes at suggested rates, K can be as high as 275-320 and P as high as 150-185. Like a lot of people I have my doubts about running those numbers because I've had good success running much lower, but it's worth testing out right?

Anyway, I think it's worthwhile to work out the formulas for elemental NPK and base the fertilizer plan on NPK ppm rather than TDS. I like the Maxibloom/Maxigro dry combo because I can get just about any reasonable n/p/k ratio I want with a 2 part formula, it contains cal and mag which a lot of dry "complete" fertilizers do not, and it's cheap compared to liquid nutes. I have attached a simple NPK calculator I whipped together in Excel. The pic should explain everything, but you can also copy/paste or delete rows. If you add rows you will need to double click the elemental PPM cells and adjust the sums to include the new rows. For different ferts, just change the names and the guaranteed analysis values. You can load in a whole nutrient line or just check the elemental values for a one part formula.

View attachment 4111948

Having run high nutrient strengths in hydroponic systems, I've found that more is not better.

Constant availability at the correct ratios is key, and I'm getting vigorous growth at lower EC values than ever, even under high light intensity, CO2 supplemented conditions.

Food for thought...

 

[ttystikk]

is your rez size altering/buffering root temps?

For my RDWC, as long as I get the water temps below 70F for an hour a day, things are fine. Letting the temperature swing upwards during the day cycle seems to help boost metabolism, as long as they get that daily cool time.

My best guess about why it works is that lower water temps boost oxygenation, helping aerobic bacteria outcompete and inhibit anaerobic bacteria.

 

[Slinging PAR]

Notes thread is a great idea. People can try what they want at their own leisure.

@ttystikk less is usually more when it comes to plants. How many pictures of overfed, over watered plants have been posted on the internet? Less electrical power, better results. Less heat, the same. CO2 can be increased with better airflow which also gets the plants strong and keeps the leaves moving to avoid hot spots.

@Evil-Mobo you probably hit and went way past your plants max DLI with those first QBs if they were all stunted. In my experience, I have found that too much light, too much heat and too cold will all stunt plants. So will too much water and ferts. If you have been successful then only change one variable at a time to isolate problems.

 

[Rahz]

Great to see you posting your notes from your garden.

Please clarify then "4/2g gallon through to week 8" from your post above.

And over 2 ounces a square foot from less than 800 umols and no CO2 is quite good in my opinion. Keep it up.

My res gets in the low 70s. But with Hydroguard I have had no issues.

That was a little vague... 4 grams Maxibloom and 2 grams Maxigro per gallon. Produces an elemental NPK ratio of 100/80/200 with the Silica. Could taper off with just Maxibloom in the last week or flush.

 

[Dave455]

That was a little vague... 4 grams Maxibloom and 2 grams Maxigro per gallon. Produces an elemental NPK ratio of 100/80/200 with the Silica. Could taper off with just Maxibloom in the last week or flush.

How about Megacrop ? any opinions ?

 

[alesh]

IS there a conversion factor yet for "LED" light to calculate Lumens to par to get PPF/PPFD etc yet? Or are we still guesstimating a number that has been agreed upon etc? I ask you this because of all the research you have done. I'm glad to see that 70CRI did well I remember picking it out in one of your threads and people looking at me like an alien LOL

There is and there's always been. There's no guessing about converting lumens to watts and/or micromoles of photons per second (µmol/s) if the SPD is known. Luminous flux is well defined through the luminosity function. Obviously, different spectrum = different convesion factor.
The problem is getting reliable data. The data in data sheets is usually just typical values with quite a large margin of error.

 

[Rahz]

How about Megacrop ? any opinions ?

Looks like a quality product, chelated and contains silica which seems unusual. 4 grams in a gallon works out to elemental NPK of 102/25/123. It's very close to Maxigro NPK numbers. Also like Maxigro it's N is primarily Nitrate Nitrogen so PH is going to climb as the plant/s feed and PH down will be needed. I would use it with a PK booster in flower.

 

[BuddyColas]

That was a little vague... 4 grams Maxibloom and 2 grams Maxigro per gallon. Produces an elemental NPK ratio of 100/80/200 with the Silica. Could taper off with just Maxibloom in the last week or flush.

Got it. Thanks. Makes a lot more sense now.

 

[thetr33man]

Looks like a quality product, chelated and contains silica which seems unusual. 4 grams in a gallon works out to elemental NPK of 102/25/123. It's very close to Maxigro NPK numbers. Also like Maxigro it's N is primarily Nitrate Nitrogen so PH is going to climb as the plant/s feed and PH down will be needed. I would use it with a PK booster in flower.

Kinda off topic but Ive got a tub of maxigro thats been setting in my shed for maybe 10 years, do fertilizers degrade if kept in a sealed container or would it still be good?

 

[OneHitDone]

Kinda off topic but Ive got a tub of maxigro thats been setting in my shed for maybe 10 years, do fertilizers degrade if kept in a sealed container or would it still be good?

if it's not all clumped up or having solubility issues I'd use it up

 

[BuddyColas]

Kinda off topic but Ive got a tub of maxigro thats been setting in my shed for maybe 10 years, do fertilizers degrade if kept in a sealed container or would it still be good?

I've used 2 to 3 year old Maxi with good result. I think the plants will let you know if your 10 year old Maxi has lost its mojo.

 

[OneHitDone]

There is and there's always been. There's no guessing about converting lumens to watts and/or micromoles of photons per second (µmol/s) if the SPD is known. Luminous flux is well defined through the luminosity function. Obviously, different spectrum = different convesion factor.
The problem is getting reliable data. The data in data sheets is usually just typical values with quite a large margin of error.

I had heard something in another lighting group circle that raised an eyebrow...
Is it possible for there to be two light sources with an equal lumen, lux, par, "output" but yet being at different "frequency".
Meaning the meter is saying the same thing but yet one is delivering that quantity of photons more than one time within the given test measurement capture period?

 

[Evil-Mobo]

There is and there's always been. There's no guessing about converting lumens to watts and/or micromoles of photons per second (µmol/s) if the SPD is known. Luminous flux is well defined through the luminosity function. Obviously, different spectrum = different convesion factor.
The problem is getting reliable data. The data in data sheets is usually just typical values with quite a large margin of error.

So then what is the conversion for "LED" and where is it listed? I have not seen this for "LED" only Metal Halide, HPS, Fluorescent, etc. I'm not trying to troll here asking a legitimate question.

 

[eyderbuddy]

Are you seriously getting that yield with only Maxibloom, Silica and Hydroguard?

No enzymes? No fungi? No Co2? No additives? No PGRs? I know hydroguard is basically bacillus Amyloliquefaciens, but damn..

If so i need to urgently step up my game...

 

[nogod_]

https://www.rollitup.org/t/math-behind.868988/

So then what is the conversion for "LED" and where is it listed? I have not seen this for "LED" only Metal Halide, HPS, Fluorescent, etc. I'm not trying to troll here asking a legitimate question.

 

[Evil-Mobo]

https://www.rollitup.org/t/math-behind.868988/

Thank you very much this is the type of information I have been looking for.

And TY to @alesh for posting that thread. Now to go read and do some math