Additional nutes/additives after switching from HPS to LEDs?

luxonator

Active Member
Hello, tiny bit of background:

EU based, English is my 3rd language so excuse me if my writing is not easy to comprehend.
I have experience with growing in soil and hydro.
I have used only HPS before and now I'm doing my first grow with LEDs. I've also switched from soil to only using hydro for the time being.


With soil I've usually used Biobizz's soil + Biogrow, Biobloom and Topmax

With hydro I have used General Hydroponics Aquafarm with 35liter reservoir + Advanced Hydroponics Of Holland (AHH) Grow,Micro,Bloom + Biobizz Topmax and some Hydrogen peroxide and PH-down when needed.

I have also used nutes from Grow Technology IONIC, General Hydroponics, Canna etc. but I always keep coming back to the AHH as it was the first one I used and it's easy to use and simple.

After I switched from HPS to LEDs, I've noticed somewhat large amounts of problems with my plants. Mainly leafs going yellow and then white (I understand this is bleaching due to the high amount of light from the LEDs), but also lots of leafs drying and then dying. Leafs with yellow patches and dark spots etc which has led me to believe it is a CalMag deficiency. And a quick googling also somewhat confirmed that. Seeing multiple people recommending CalMag additives while using LEDs. Whether or not this to be considered a gospel that everyone needs to follow is up for debate.

Anyway, to the point: Is there some additives that are universally considered a *must* while growing weed with LEDs in hydro? Most of my life I've been growing with just the basic 3 part set with an addition of some kind of bloom booster (Topmax) and sometimes some sort of root stimulator at the beginning of the grow.

I've taken a look what the local grow stores offer now and there seem to be sooo many additives and borderline snake oil -grade stuff. Do I really need some sort of "PK-booster" or "Aminoacids" additive and CalMag and Enzymes and 3 different carbohydrate/molasses type "bloom booster" things?

I was under the impression that hydro nutes designed for growing weed already have the correct amounts of N-P-K which you adjust by changing the dosages in different stages of growth/bloom. So why would I need an additional PK-additive?

I've also noticed lots of "tribalism" between people using certain brands hyping and bashing products like there is no tomorrow. I understand brand loyalty and all of that, but for me it's not really an issue, I can buy and use whatever product is proven good and has good price/performance/quality ratio.


tl;dr
Sorry, I'm rambling. My main question is: What would you suggest for me to add to my hydro nutrient schedule besides just the 3 part base nutes with a some sort of root grow booster and added sugar/molasses-type bloom booster at the end? The consensus seems to be that some sort of CalMag additive is needed, but what about those PK-boosters or Enzymes etc? I don't want to get 3 different bloom boosters etc, just the essentials that actually have noticeable effects on the crop.
 
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Boatguy

Well-Known Member
I have never grown under hid, and have never had a need for any sugar/molasses. Some add those sort of things for their soil health, no idea what kind of benefit it would have on hydro
 

Herb & Suds

Well-Known Member
First WELCOME to RIU
Second
There is no reason to use hydrogen peroxide in soil :spew:
Third your plants aren’t bleaching due to HPS
I’m almost afraid to ask where you have been getting this bad information?
 

luxonator

Active Member
First WELCOME to RIU
Second
There is no reason to use hydrogen peroxide in soil :spew:
Third your plants aren’t bleaching due to HPS
I’m almost afraid to ask where you have been getting this bad information?
Sorry, I think my post was unclear or confusing. I'll edit my post for clarity.

I only use hydrogen peroxide in hydro.
My plants started to bleach ONLY AFTER I made the switch from HPS to LEDS. I had *never* seen bleaching on my plants while I was growing with HPS.

Again, for clarity: I'm now growing with only LEDs and hydro.
 

Herb & Suds

Well-Known Member
Sorry, I think my post was unclear or confusing. I'll edit my post for clarity.

I only use hydrogen peroxide in hydro.
My plants started to bleach ONLY AFTER I made the switch from HPS to LEDS. I had *never* seen bleaching on my plants while I was growing with HPS.
Maybe I just read it wrong

old eyes and brain :p
 

luxonator

Active Member
I have never grown under hid, and have never had a need for any sugar/molasses. Some add those sort of things for their soil health, no idea what kind of benefit it would have on hydro
My understanding and experience with different bloom "enhancer" / "booster" products that usually consist of sugars and/or molasses and fulvic/humic acids is that they increase the size of the buds a little bit and improves the taste and increases the amount or trichomes (by either giving the plant more sugars or promoting cell division and other marketing jargon) . How much of this is just placebo, I cannot say. But I've been using them for decades without any ill effects.

I've been very happy with the results of Biobizz's Topmax and if my local grow store has run out of it I've replaced it with either Aptus' Topbooster or GHE's Biobloom. One bloom enhancer is all I've needed.

They all do and are aimed more or less at the same thing. That's one of the reasons why I'm perplexed about why some nutrient lines seem to have multiple products that are doing more or less the same thing (looking at you Advanced Nutrients with your Budcandy, Bigbud, BudfactorX, Overdrive etc etc... All are for "bigger and better buds").

But again. ~20 years ago or so I can't recall seeing any "pk-boosters" and whatnot aimed towards weed growers. I understand there must be a market for these products as otherwise they wouldn't exists, but when does one actually need these?

But I digress, my original question still stands. Besides lowering the light intensity or putting the LEDs higher to prevent bleaching and adding some CalMag-product to help battle/prevent the leaf problems I've now encountered, I guess there isn't really any need to add anything else into my feeding schedule?

The thing that made me write this thread in the first place was that when I googled "LEDs calmag" I got lots of results where the general consensus was that if you grow with leds, additional Calmag is almost necessary and lots of people had encountered calcium and/or magnesium deficiency while using LEDs.

I'm not saying this is set in stone or the word of God, but it does correlate with my own limited experience with LEDs.
 
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HippieDudeRon

Well-Known Member
The most common increased nutrient going under LEDs is magnesium. 60ppm or so total seems to be enough. Some use more if needed.

But really sounds like you have environmental issues, light intensity, temp, RH, DLI.
You said "I understand this is bleaching due to the high amount of light from the LEDs"... What is that intensity you have going on? HPS and LED?
 

hotrodharley

Well-Known Member
My understanding and experience with different bloom "enhancer" / "booster" products that usually consist of sugars and/or molasses and fulvic/humic acids is that they increase the size of the buds a little bit and improves the taste. How much of this is just placebo, I cannot say. But I've been using them for decades without any ill effects.
Molasses is almost useless. It began as a source of humic acid for the beneficial microbes. There's far better. And fulvic/humic add more than a little bit. Fulvic aids in nutrient uptake by the plant while the humic feeds the beneficials which are also helping transfer nutrients from the medium through the roots.
 

Rurumo

Well-Known Member
One of the big things you need to do is keep your temperature higher, try at least 80 deg F during light's on, and 75 off. Try that before bothering with calmag supplements because the plants need those temps to metabolize CA. You also need to find the right distance for your light, sounds like you are keeping them way too close. Try 24 inches or so and go from there. Magnesium seems to be needed in greater amounts under LEDs, as others have said here, I do add additional epsom salts to my nutes under LED.
 

farmerjoe420

Well-Known Member
Sorry, I think my post was unclear or confusing. I'll edit my post for clarity.
LED bleaching is a real thing. Don’t listen to anyone telling you otherwise. When switching to LED you need to make changes, mostly environmental. Also, you will need to adjust nutrient strength as well as have a understanding of how much light your plants are actually getting.
To get the most out of LED and really dial things in I would recommend this

1. environment -

- Raise your ambient room temperature to around 82-84 F. LED doesn’t heat up the plants leaf surface in the same way HID does so raising ambient temperatures help a lot.

- Use a VPD chart and try to optimize your humidity in line with your temperatures according to the chart.

- you will likely need a dehumidifier and I would highly recommend buying a light meter so you can begin to understand how much light your plants get and if your giving them too much.

2. nutrients -

- LED gives off more usable light so naturally , the rate of photosynthesis will increase. You will need to make sure your plants have adequate nutrition to support a higher rate of photosynthesis. If you already use a well balanced nutrient with proper ratios , increase overall EC and dont just increase single elements like magnesium. Your plants are going to need more of everything.

Last, if you really want to compliment it all, add Co2. At a certain point of light saturation, CO2 is the last piece of the puzzle to get the most out of the higher light intensity. If you have any more specific questions feel free to send me a message.
 

luxonator

Active Member
You said "I understand this is bleaching due to the high amount of light from the LEDs"... What is that intensity you have going on? HPS and LED?
I was using 600W HPS in a 4x4 tent (never measured the PPFD from it). Now I have 2 x 255W SANlight leds that give me around 500-800 PPFD (depending where I take the readings) according to my not so accurate meter on my android phone (PhotonE). Will have it calibrated in the future for better accuracy.
Temps are 20-26C (68-79F) and RH is 20-40%

Literally the only change I did for my setup was switching the HPS to LEDs.
 
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