Nutes and PPMs in DWC discussion

Hey All, I've been really struggling to get the correct PPMs on my bubbleponics system. First, a little background info on what I've got...

4 plants, all AK-48 (Indica)
5x5 mylar tent, 600W HID always about 19" from canopy top.
4 plants in 80 L of DWC water in 3" trays, several large airstones. Water change every 8 days. Water sits 1" below bottom of trays.
Air Temp: 23 C - 33 C
Water temp: 68F-79F
Nuts: Advanced Nutrients SensiGrow Parts A+B only currently.
My tap water was 190 PPM, I put in a bit of nutes and I started off with a PPM of 300 and a pH of 5.8-6.3...everything was going great and things looked like this by the 28 day mark:
View attachment 1529419

Then on day 33, I was at 480 PPM and N-deficiency started. it spread FAST! Some folks told me to drop my pH and up my PPMs, so I did that. The damage spread until the plant adjusted to the new levels; by day 36 my PPMs were at 750 and pH was at 5.3-5.8. The spreading of N-deficiency now has either slown down to a crawl or stopped...honestly its hard to tell and it makes me nervous. Now i'm like 3-4 days from flowering. Problem is, I have now seen mild signs of nute burn! So before it was too low and now its too high.

I wanted to get some DWC/bubbleponics growers two cents on PPM levels and feeding schedules. I tried using the method of watching whether the plant drinks the nutes as it drinks the water, but at that method, 480 PPMs were looking fine until the N-deficiency started. Some more pics of my grow between days 33-35 just for fun:

What's your starting and ending PPM?

i'd put a 600 watter closer than 19". i keep my 1000 watter about that distance. your feed strength seems way low to me. i grow hydro, and at this point, i'd be at full strength of around 800-1200 ppm. they actually look hungry! in hydro, optimal ph is 5.8.

You would go full strength before even reaching flowering stage? isnt that too soon?

no Im sitting at 1150 now and tomorrow Ill be going up to 1500 with 25% flower nutes. with that said It looks like some of yours wouldnt like that to much as the signs of brown leaf tips. ( now this is only my opion as im no pro)

NorthernLights#5 said:

with that said It looks like some of yours wouldnt like that to much as the signs of brown leaf tips. ( now this is only my opion as im no pro)

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i didn't see brown tips but it is def. a sign of ppm being a couple hundred high...

lookin like you got it. should start blowin up soon.

The pictures i posted up are from three days ago. There are brown tips on many leaves now, though they are very mild. Also lots more leaves than in the picture ended up yellowing due to the N-defiency. That's why i'm kind of wondering. I slowed down the N-deficiency turning the leaves yellow by moving the PPMs from 450 to 750...it's all but stopped. but it caused some brown leaf tips. There doesnt seem to be a comfortable middle-ground so i'm hoping to get a few people's PPM increments/week for their DWC.

when you see/get nursery burn/brown tips, just back off the ppm about 2 hundred.

Silky Shagsalot said:

when you see/get nursery burn/brown tips, just back off the ppm about 2 hundred.

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That's precisely the problem though....I had extreme N-defiency at 480 PPM or so....i only bumped it up to 780 PPM and the tips all over the plant got slight burns as a result...if i back off by 200 PPM i'll go back to the N-deficiency. And I'm not even sure that going up to 780 has stopped the N-defiency. Its been 5 days and so far i'm still seeing more yellowing, its just much much slower.

Flo Grow said:

You both have it wrong.
You shouldn't increase PPM's by more than 100 pts at a time over a few days.
Even an increase of 50 will/can show burning.
All that back and forth is gonna stress them more and decrease your dry yield.
If your plants are green and lush, then let them be.
Even plants from the same seed stock can react differently and be more/less sensitive to nutes than it's sisters in bloom.
Each plant is an individual living thing with no two being/growing completely alike, even in a stabilized strain, unless they are clones and they even get funky !!

Some growers crack me up cranking their plants to their "max" feeding thinking it'll get them fatter buds.
It's not like stuffing a human being with food.
It doesn't work that way.
Growers are still hurting their dry weight because the plant is being bombarded with excess food.
It will always take what it needs and the rest is waste.
Very, very few strains ACTUALLY require/want a high EC/PPM/TDS.
MOST can and will give the optimum results in the 800 - 1100 PPM range.
The more nutes your force into the plant, the less water it uptakes and therefore it's metabolism gets slowed down and that DECREASES nutrient transport bcuz the nutes NEED water to move through the plant.
Excess nutes = less water uptake = less transpiration = less photosynthesis = less growth = less harvest !!!

I start my seedlings in 100 - 250 ppm's......strain dependent
Veg stays under 700 ppm's
Bloom ppm's are up to the plant and what it's asking for, but not every strain needs 1300+ ppm's.

Just my 2 cents.
Few will listen, while most will keep doing the same thing over and over expecting a change and THAT is the definition of insanity !!! lol

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Your the man. Rep.

yo Flo Gro...you say you start at 100-250...what type of water do you use for your DWC? I use tapwater and it's 190 right out of the tap. so i start off at 300 PPM after the nutes go in.

Flo Grow said:

You both have it wrong.
You shouldn't increase PPM's by more than 100 pts at a time over a few days.
Even an increase of 50 will/can show burning.
All that back and forth is gonna stress them more and decrease your dry yield.
If your plants are green and lush, then let them be.
Even plants from the same seed stock can react differently and be more/less sensitive to nutes than it's sisters in bloom.
Each plant is an individual living thing with no two being/growing completely alike, even in a stabilized strain, unless they are clones and they even get funky !!

Some growers crack me up cranking their plants to their "max" feeding thinking it'll get them fatter buds.
It's not like stuffing a human being with food.
It doesn't work that way.
Growers are still hurting their dry weight because the plant is being bombarded with excess food.
It will always take what it needs and the rest is waste.
Very, very few strains ACTUALLY require/want a high EC/PPM/TDS.
MOST can and will give the optimum results in the 800 - 1100 PPM range.
The more nutes your force into the plant, the less water it uptakes and therefore it's metabolism gets slowed down and that DECREASES nutrient transport bcuz the nutes NEED water to move through the plant.
Excess nutes = less water uptake = less transpiration = less photosynthesis = less growth = less harvest !!!

I start my seedlings in 100 - 250 ppm's......strain dependent
Veg stays under 700 ppm's
Bloom ppm's are up to the plant and what it's asking for, but not every strain needs 1300+ ppm's.

Just my 2 cents.
Few will listen, while most will keep doing the same thing over and over expecting a change and THAT is the definition of insanity !!! lol

Click to expand...

preach it cuz!!
how do people think this stuff grows in the wild?
just animal pee and poop with some rain. a lot of the times just rain and it's still bomb ass bud.

aleksandr2010 said:

yo Flo Gro...you say you start at 100-250...what type of water do you use for your DWC? I use tapwater and it's 190 right out of the tap. so i start off at 300 PPM after the nutes go in.

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I use R/O water because my tap is 250 ppm's, and I want to know WHAT is feeding my plants.
Only prob with R/O is you need to add Cal/Mag bcuz those 2 macro nutes get filtered the most versus other minerals.
I use the water machine at the supermarket.
A 5gal bottle lasts me about 1 week once they hit bloom and starting gulping water.

pwizzle said:

preach it cuz!!
how do people think this stuff grows in the wild?
just animal pee and poop with some rain. a lot of the times just rain and it's still bomb ass bud.

Click to expand...

Exactly friend ! lol
Growing with 2 - 3 part grow nutes and 6+ other additives that aren't needed really !! lmao

Flo Grow said:

You both have it wrong.
You shouldn't increase PPM's by more than 100 pts at a time over a few days.
Even an increase of 50 will/can show burning.
All that back and forth is gonna stress them more and decrease your dry yield.
If your plants are green and lush, then let them be.
Even plants from the same seed stock can react differently and be more/less sensitive to nutes than it's sisters in bloom.
Each plant is an individual living thing with no two being/growing completely alike, even in a stabilized strain, unless they are clones and they even get funky !!

Some growers crack me up cranking their plants to their "max" feeding thinking it'll get them fatter buds.
It's not like stuffing a human being with food.
It doesn't work that way.
Growers are still hurting their dry weight because the plant is being bombarded with excess food.
It will always take what it needs and the rest is waste.
Very, very few strains ACTUALLY require/want a high EC/PPM/TDS.
MOST can and will give the optimum results in the 800 - 1100 PPM range.
The more nutes your force into the plant, the less water it uptakes and therefore it's metabolism gets slowed down and that DECREASES nutrient transport bcuz the nutes NEED water to move through the plant.
Excess nutes = less water uptake = less transpiration = less photosynthesis = less growth = less harvest !!!

I start my seedlings in 100 - 250 ppm's......strain dependent
Veg stays under 700 ppm's
Bloom ppm's are up to the plant and what it's asking for, but not every strain needs 1300+ ppm's.

Just my 2 cents.
Few will listen, while most will keep doing the same thing over and over expecting a change and THAT is the definition of insanity !!! lol

Click to expand...

Cant thank you enough for this