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Making Your Own Nutrient Concentrates

Skybound

Well-Known Member
This is my attempt to compile and condense all of the information I've collected from other grower sites and share it here on 420 in hopes of generating more feedback and ultimately learning more myself. I grew with General Hydroponics for years, but could never seem to nail down a perfect feed regimen and always had at least 1 or 2 minor deficiencies, so I set out to try a new line, but I'm a cheap skate and an internet friend I met on my most recent journal convinced me that I'm buying water, so I set out to learn how to make my own.

Before I get too far ahead of myself, I do need to point out that none of my recent successes would be possible if not for learning how to use Hydro Buddy that was created by Daniel Fernandez PhD. He created the free software that we can use to calculate water soluble nutrients expressed in "elemental ppm". Elemental PPM is the measure of each element that is included into a component, and when using several components to fill out a recipe, the math can get quite intense which makes using this free app so useful, especially to potheads.

So before I delve into my findings, I will attempt to give a step by step to use the app to calculate some popular lines of nutrients, so we can analyze the results, and compare each to the next, and also the regimen that I've created and am now using.

To start, download and install Hydro Buddy. As far as I know, this app only works on PC, Unix, and maybe Macbooks, but I'm certain the app does not work on phones, so if that's the only device you have to use on the web, I feel your pain! still, you'll have to locate a computer to use the app.

Hydro Buddy Download

After the app is installed, open it and click on the "Main Page" tab.

Main Page.png

Once there, take notice of the areas I have circled. All of the nuts and bolts are beyond the "Substance Selection" tab, but my practice is to first click "Zero all targets", then I proceed to set my "Volume". You can then set it to 1, 5, 10 whatever size your res is, but I set it to "1", and I tick the field next to gallons as I live in the states, though liters is said to be more accurate and since it will boil down to milliliters anyways, we end up in the metric system anyways. Another reason I use "1" "gallon" is because I am mixing up my own concentrates, and that's the size I mix each time to suit my small grow. Once your targets are zeroed and your volume set, you can now click the "Substance Selection" tab.

3 directions.png


Set Weights.png


For some reason, the Substance Selection window defaults to half way down my screen and I need to reposition it so I can see everything. We take the good with the bad, right? To demonstrate, I loaded up most of the GH Flora series line. I'll show how to create/edit each shortly, but for now, this is where you have 2 basic options.
  • You can leave the weights set to zero, and when setting "Targets" on the main page by going through certain elements that you wish to target, with the macros N-P-K being the highest priority in the final composition, the app will crunch all of the numbers saved into the components you have listed in Substance Selection, in this case the components of the GH Flora series line, and output the exact dose you'll need of each to hit your targets. This feature alone will make tweaking your nutes on hand to the most optimum ratios possible and allow you the ability to actually respond to what your plants are telling you about the feed you've been giving them. Need more N? move your target for N up a few ppm.
  • You can "Set Weight" to build your own nutrients from salts, or if you want to test an existing line to see exactly what they got in there and compare one to the next, this is where you'd do that. To reverse engineer a line of nutes, you'll need to click on "Add Custom", and create a new substance. I'll explain all that shortly, but for now, assume it's done as I have already done so with GH, AN, Botanicare and a few others.
Once the weights have been set or zeroed (or both), you'll close the Substance window. I double check that I have my targets set as I desire, then click the "Carry Out Calculation" button on the lower right. Shortly after, a few popup windows appear alerting you if any of your listed substances were not used in the results, and finally that the calculation was successful. In the column to the right of the targets is the total "elemental PPM" results of everything used combined, so this is where you visually see the difference between your target and the result. To look at additional data points such as amount of each substance used, degree of error in percentages as well as the resulting EC. Please note that the app displays "elemental PPM" which differs from TDS which we growers always communicate as PPM. The results of this demo show the EC to be 1ms/cm, and when using a TDS pen that has a conversion factor of .5, the TDS display should be very near 500, but in reality my meter displays near 750. There are obviously other contents in the bag or bottle that are not included in the label's "Guaranteed Analyses" (GA) that we are not programming into the app, so to expect the app to somehow correctly guess what the difference is is just not practical. That said, prepare yourself to have the difference between PPM and TDS shown to you in application and observation.

results.png

Being as though I zeroed the weights of the GH line, and relied on the app to compute the best result from the targets I gave it, the Results tab "Mass column" listed in grams can is also translated into ml evenly because the "Density" was factored into the information I gave the app about the Substance. This is learned when comparing the weight of the volume of deionized water (1 gram per ml) versus the actual weight of the substance as listed on the front of the bottle. If 1 US gallon has 3785.41 ml, then the weight of that amount of deionized reverse osmosis (RODI) water should also be 3785.41 grams. We can divide that by 4 to realize quarts, or simplify the math totally when using the metric system as everything's divisible by 10, so simply moving the decimal left or right is needed. The difference between a bottle of RODI's weight and the bottle of nutrient's weight is the density, and this factor as added when you create your own Custom Substance. So this is how I know that 2.4 grams will translate into ml, as the volume was also added in on the Main Page.
 

Skybound

Well-Known Member
To create a Custom Substance from the Main Page, click Substance Selection, then in new window click "Add Custom"
Add Custom.png


Once the new window opens, you can type in the name you want to give it, the formula if you want it to be displayed, but when inputting liquid nutrients, you need to check the field next to Liquid. Doing so makes the Density field appear and this is where you would input the result of dividing the weight of the volume of nutirnet by the weight of the same volume of RODI. The result is the density. Usually 1 or 1.1, something like that. It is also important for some reason that the Purity be set to 100. It's likely that Purity means something else, but I didn't learn that yet.

Also, when creating custom substances, both wet or dry, you will need to reference the Guaranteed Analyses (GA) listed on the product label. The GA will tell you in percentages how much of each element is contained. Some things have micros, some don't. P and K, are usually listed as either P2O5, or K20 and you'll want to select each accordingly in their drop down menus. Silica also has a drop down that will be used the same way as Silica is delivered using K and will influence the final values. P and K, undergo a conversion factor which multiplies each by a known decimal to derive at available P and available K in the final recipe, otherwise the app will assume that other sources of each were used and will not be immediately available and will greatly affect the Result.

Edit - As a reference point, I'll include a screenshot of GH Flora Micro. Please note that the K has already been converted from K2O.

Micro.JPG
 
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Skybound

Well-Known Member
This is the notes I've collected, much of which was picking a grower's brain on another forum, but the content so far checks out against other growers on that board as well as what I'm seeing in Veg and Bloom. I will paste my notes, and add commentary in black where I feel the need.

Values, Ratios and Recipes

-----------------------------------------------------------------------------------------------------
* MKP(monoPotassium Phosphate),
* FHK(Fulvic/Humic/Kelp Blend)----------------I use this to swap out Flora Blend and Floralicious Plus. Plants love it.
** .25TSP FHK = 0.9g-----No longer important, just weighed it in case.
** ml/Gal = 3785.41
** ml/Qt = 946.35
** Calories of Sugar = 15/TSP --- Carb = 4Cal/g

*** Jack's A is 5-12-26

You can figure the ACTUAL amount of P by multiplying the label# by 0.44 and the K amount by 0.83.
^^^This is the refactoring P and K go through in Hydro Buddy

My feed tops out at 1ms, though the individual I gleaned most of this info from suggested these ranges
0.6-0.8 ms --- Cuttings/Seedlings
1.6-2.0 ms --- Veg
1.6-2.3 ms --- Bloom

Veg Ranges ------My feed was constructed using these Veg/Bloom ranges. So far, good everything, maybe slight K def. More observation is needed to know for sure.
N 110 - 120
P 30 - 40
K 120 - 130
Ca 80 - 90
Mg 40 - 50
Fe 1.3 - 2

Bloom Ranges ---- These levels look spot on. It even stopped a calcium deficiency I've been trying to remedy for months using GH.
N 65 - 90 (never less than half of K)
P 40 - 65
K 130 - 150 (130 max for coco)
---
Ca 65 - 90
Mg 40 - 50
S 50 - 80 *** (lowered from 64/148)
---
Fe 1.5 - 2 --------------Fe is the last range I was able to extract in my Q&A sessions. The remaining ranges I gathered from comparing Hoagland's and Steiner's formulas. I am also looking at GH and other lines to see how far away those are, if growers are having success with them, and if any dillution is being utilized. I just keep collecting intel when possible to learn more.
B 0.5 - 2.0 ***
Mn 0.5 - 2.0 ***
Zn .05 - 0.2 ***
Cu .02 - 0.5 ***
Mo .01 - 0.1 ***
*** inspired by Hoagland's and Steiner's formulas
-------------------------------------------------------------------------------------
I added GH next to Hoagland and Steiner to see how they compare.
--------------------------------------------------------------------------------------
Hoagland's Bloom--|Steiner's formula--|GenHydro Mid Bloom
N 210 ppm---------| N 170 ppm--------| N 125.482
P 31 ppm-----------| P 50 ppm----------| P 103.756
K 235 ppm---------| K 320 ppm---------| K 262.153
Ca 200 ppm--------| Ca 183 ppm-------| Ca 165.108
Mg 48 ppm---------| Mg 50 ppm--------| Mg 85.856
S 64 ppm------------| S 148 ppm---------| S 46.23
B 0.5 ppm-----------| B 1 to 2 ppm------| B 0.198
Fe 1 to 5 ppm------| Fe 3 to 4 ppm-----| Fe 3.302
Mn 0.5 ppm--------| Mn 1 to 2 ppm----| Mn 0.991
Zn 0.05 ppm--------| Zn 0.2 ppm--------| Zn 0.297
Cu 0.02 ppm--------| Cu 0.1 - 0.5 ppm-| Cu 0.198
Mo 0.01 ppm-------| Mo 0.1 ppm--------| Mo 0.159
--------------------------|-----------------------------| Si 30.935
--------------------------------------------------------------------------------

(PPM)
110-35-120 veg
90-45-130 early bloom
75-60-130 bloom
65-65-130 late bloom (Lucas formula)

(example)
veg - 110-35-120 = 265
early bloom - 90--45-130 = 265
late bloom - 75--60-130 = 265

PH goes up and EC goes down = raise EC (maybe)
ph goes down or EC goes up = lower EC
--------------------------------------

Just doing simple math to get these numbers. I am currently using the 1:10 concentrate which allows me to extract fractions of a gram with a syringe instead of a scale. For instance, 0.345 grams would be 3.45ml. Easy peezy! I assume the measure of a gallon of water to be a true gallon as I have not personally pumped in almost 3800ml of RO to verify. That said, I work out the mixture in math. I already know how much weight to add to the water, but I'm not sure how much the volume will increase by adding the salts. What I do, is put the salts into a solo cup, then deduct an equal amount of water in volume and put that off to the side. Then mix in all the salts till completely dissolved, then top off the jug with how much ever water is needed to bring the level back up to a gallon. This ensures the weight added and the combined volume to be a gallon, or whatever metric you're using for volume. I made the middle black for ease on the eyes.
Making Concentrates 3785.41 ml/Gal
1:10 --------------------- 378.54 grams (mild ratio for ease of accuracy)
1:5 ---------------------- 757.08 grams (moderate ratio for larger systems)
1:2 ---------------------- 1892.70 grams (liberal ratio)
1:1 ---------------------- 3785.41 grams
---------------------------------------------------------------------------------
Some recipes I found elsewhere. GH was on the bottle. I had great results from this one when using it. It made the Kush smell so damn fruity, almost like grape juice if that makes a little sense.
-----------------------------------------------------------------------------------
----------GH Flora Nectar Fruit-N-Fusion
0-0-1-------------------826ppm, 2.85pH
1% Soluble Potash(K2O)
0.5% Water Soluble Magnesium(Mg)
0.5% Combined Sulfur(S)
Derived from Magnesium Sulfate and Potassium Sulfate
To Feed Soil Microbes;
17.5% Cane Sugar
5% Molasses
I read Potassium Sulfate enhances the lemony scents and Magnesium Sulfate (Epsom salts) enhances fruity scents.
----------Terpenator;
1 Gallon RO
378.5 grams Potassium Sulfate
1.5 TSP Dark Brown Sugar---(22.5 Calories)

STARTING Week 3&4
4-ml in 1 gallon of your feed
At week 5&6
6-ml in 1 gallon of your feed
At week 7 till harvest
8-ml in 1 gallon of your feed

---------------------------------------------------------------------

-------------
MolassesAfter filtering out plant trash and raw sugar crystals, millers slowly evaporate the liquid, resulting in a rich, brown mixture called molasses. Molasses contains 46 percent dissolved sucrose and other sugars; 3 percent protein; small amounts of minerals like calcium, phosphorous, magnesium and sulfur; trace elements such as copper, iron, manganese and zinc; and B-vitamins. Molasses is used for both human and animal consumption. Producers may also mix it with raw sugar to facilitate transport to a refinery, or with white sugar to yield brown sugar.

Brown Sugar

Mixing white sugar crystals with various amounts of molasses results in a soft, lumpy product called brown sugar. The amount of molasses added depends on the producer, but you could expect light brown sugar to contain 3.5 percent molasses, while dark brown sugar might contain 6.5 percent molasses.Brown sugar imparts the taste of molasses to recipes and adds moisture to make a softer texture.
 

Skybound

Well-Known Member
Here are the feed charts I plotted out using Hydro Buddy. Aside from using a fulvic, humic, kelp blend I got from "Kelp4Less", I only use 6 components (Substances). The main part I currently use is Jack's Hydro 5-12-26. I picked up a Kg for about $15 I think, just to get me started. I saw 25 pound bags on Amazon for about $80 and it will last me for the rest of my life, or damn close. Jack's was originally called JR Peters, as Jack is one of the sons of Mr Peters. He since sold the family business to whoever, but then still has his own business with the same line he had for many years. I don't fully understand that dynamic, but don't care enough to investigate it further. Jack's Hydro has all of the needed micros at fair levels from what I can see. The feed is just a matter of getting in more N, P, K, Ca, Mg, S and I intend to bump up my micros very slightly in the near future. For the most part, the remaining components each have 2 of those 6 elements, and all together finish at near perfect levels relative to my targets. So here's the whole lineup.

FHK (Organic Chelates)

Jack's Hydro 5-12-26
Calcium Nitrate (cal nite) 15-0-0 (18% cal)
Magnesium Nitrate (mag nite) 11-0-0 (9.6 mag)
Monopotassium Phosphate (MKP) 0-52-34
Magnesium Sulfate (Epsom Salt)
Biomin Calcium Powder 5-0-0 (15% calcium)

The Biomin technically is another Cal Nite. With those 6 components, I can hit every target leaving only sulfur out in the wind. If I so desire, I can zero all the weights of my components, but then go in and set a desired weight to any of the components, then have the app compute the tally with that weight in mind. This would allow me to force the app to use more epsom to increase the sulfur, but then some of the other targets would be missed as a result. Still though, being as we are solely focused on generalized ratios, most elements should be able to handle a higher degree of error, so long as it's not too far outside of the desired ranges, and like everything else about growing, nothing is set in stone. there are wide and forgivable tolerances everywhere, especially when comparing my notes with my findings when rev engineering other nutrient lines and seeing those levels.

I've found when ordering Jack's nutes from their site jacksnutrients, the box that arrives in the mail has a very large very well defined sticker that proudly displays the contents in this box were sent from ((((JACKS HYDROPONICS))))), so if you have nosey neighbors, perhaps consider other brands or locate Jack's on Amazon or elsewhere. I see other growers mixing with the tomato 420 blend which is 4-20-38. I'm considering trying Mega Crop as others use it as a stand alone with great results, so I can only hope to complement it where needed. I'm sure in my journey's I'll eventually try them all in search of the best combo for the cheapest. I found the Calcium Powder which is chelated with Aminos, the mag nite and the other stuff from a site called customhydronutrients. Their shipping is very discrete, and so too is Kelp4Less. Custom hydro has all the salts, and Kelp4Less has the organic stuff, as well as some salts as I got my MKP there too. I also have my eyes on the Micro Nutrient Pack to slightly beef up the jacks. I have a few things on the wish list for sure, but right now, my feed is performing flawlessly. I have 2 Kush in bloom, one of which gets harvested tomorrow and the the final one that looks very good compared to her previous generations. I have a Triple Cheese in veg that has already been cloned out 3 times and is aching for the that spot to open up in bloom tomorrow. I've never grown a plant that stayed so green for so long. I am greatly impressed even though I still see room for improvement.

Well, that about wraps it up. I think I added all that I can to the topic. Oh shit, I forgot, here is my feed charts using the above components. EC of 1ms translates into about 750 ppm on my TDS meter at .5 CF. I've been running this strength from early/mid veg till harvest, and just moving the ratios around inside. So when I mix up 10 gals, I plan for 10 gals with no dillution.

Veg and Trans.JPG
Bloom.JPG
 

Skybound

Well-Known Member
It's definitely a lot, but there's so much more. We can't test for individual elements sadly, but the people that can, manufacture the nutes we use, and I assume there's something of a guarantee in their Guaranteed Analyses. As for the purpose of this thread, I just wanted to share how to use Hydro Buddy because I had the app for years, and only recently learned how to use it, and I'm so excited, I just had to share it. The app IMO, is kickass! I could have easily remained buying water from General Hydro had I learned how to use the app before switch brands due to my new ability to alter their feedchart to get out of it what I need versus what they intend to give me. That feature alone makes this an amazing app. The fact that it's free is just that much more amazing.
 

Tead

Well-Known Member
I kinda think the implementation of the Guaranteed Analysis system exists to address the needs of various growers not wanting to have to deal with the testing. Kind of along the lines of the Underwriters Labs system.
You're a pain in my ass already. Downloaded the app. Gotta wrap my head around it some so I can even speak to it at all. Killin me.
 

Skybound

Well-Known Member
The above schedules for the 2 veg stages, trans and 3 bloom stages are bogus. The NPK and secondaries are spot on, but the micro nutrient levels are much too low and I began noticing Zinc deficiency in my plants. Thankfully, I have about a gallon of GH Flora Micro and was able to elevate my micro levels to a more reasonable range. I'm slowly beginning to see the ideal ranges for micro nutrients and am confident in saying that predominantly, everything should be in the 0.2-0.5 elemental PPM range. Some a bit higher and Molybdenum lower than 0.2.

Here are my bloom ranges and targets when I plan to make a weekly batch. Be mindful that for early bloom I aim for high N and K, after stretch, I pump up the P and as the weeks progress, I lessen the N and Ca. To finish I aim to also reduce P and leave the K high throughout. The micros stay about the same throughout except Sulfur which I'm wanting to see how high I can push that as Sulfur is responsible for odors.

Refined Nutrient Ranges.JPG
Example Charts.JPG


I'll be getting a micro nutrient supplement called S.T.E.M., though I don't recall what the letters stand for except the M means Micro of course. So far, based on my research, I don't believe Jack's 5-12-26 and STEM will give me the most ideal ratio of micros, but several growers that have used those 2 components together said they didn't notice any adverse effects, so I'll take that as a green light, and just continue to search for more ideal products down the line.

As an example though, I will select all of the components I will have next week with the STEM, and my target ranges for Mid Bloom with elevated P and K, moderate N, plus silica, and let's see what my results are.

mBloom Targeted.png
mBloom Results.png


So it looks like the ratios of micros is a bit high for my liking, so I might take it upon myself to either add less STEM to the overall mix, or set the weight in the app to a bit less than is resulted here, then recompute to see how much closer to my ranges I can get everything. Then rinse and repeat till I can get it as close as I can.

That's what I love this app so much. It makes it SO easy to analyze my feed charts as well as other brands to compare and see what's working for people, and what isn't. Even when treating a nutrient imbalance in the past, I never really knew what I needed to do to the feed schedule to correct the errors, now I do.


S.T.E.M. = Soluble Trace Element Mix
 
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Skybound

Well-Known Member
Due to jack's nutrients shipping packaging, I decided to order a similar, but not same, product from customhydro called Peter's Professional which has 1% less P, and a bit less Epsom Salt for Mg and S. When plugged those numbers into Hydro Buddy, as well as the numbers for S.T.E.M., I set my targets for a Transition feed into 12/12 and I was greatly pleased to find that the results of the trace elements were damn near perfect on my targets for those.

Iron (Fe)
Zinc(Zn)
Boron (B)
Manganese (Mn)
Copper (Cu)
Molybdenum (Mo)

What this means to me is that I believe I've found the perfect combo of base nutrient, leaving only the macros and secondaries to be filled out with more robust 2 part ingredients such as "monopotassium phosphate (MKP)", "Calcium Nitrate", "Magnesium Nitrate", "Epsom Salt (magnesium sulfate)", "Potassium Silicate" and "Chelated Calcium Powder (inverted Cal Nite)". I find it's much easier to hit the larger targets which will make it much easier to adjust the larger concentrations individually.

Peters Pro w-STEM.JPG
 

Skybound

Well-Known Member
I'm glad someone commented here as I need to update the info a bit. For starters, I discontinued using the fulvic/humic/kelp blend due to it gunking up my res. I even mixed it in a concentrate to let it settle there, and I was just drawing from the top, but the kelp in the mix over time began to turn and smell like shit. I intend to get the blend of fulvic/humic with no kelp in the future though as my grow has definitely slowed down since I stopped using it. Kelp4Less has an awesome selection of organics.

I also stopped using Biomin Chelated Calcium because I misread the label. It is only for slow release soil or foliar applications and not for hydro. For a while I was getting calcium deficiencies and for the life of me could not figure out why until I reread the description and it hit me.

I also stopped trying to use potassium sulfate. I suppose if I set my K target stupid high, Hydro Buddy would use this product, but down in the stable ranges it simply will not use it.

I now only use the following 7 products;

Potassium Silicate
Peter's Pro Soluble Trace Element Mix (STEM)
Peter's 5-11-26 (same as Jack's 5-12-26 with a bit less S and Mg)
Calcium Nitrate (CalNit)
Magnesium Nitrate (MagNit)
Monopotassium Phosphate (MKP)
Magnesium Sulfate (Epsom salt)
I use Peter's over Jack's because I am able to source everything listed above from CustomHydro and they ship discretely. I once ordered from Jack's directly, but their packaging tape plus added stickers proudly states that the contents in the box are Jack's hydroponic nutrients and I just don't want that kind of attention.

With the above components mixed as listed below, my PH settles to 6.2-6.3. I make 10 gal reservoirs for bloom, mix to 100% and the TDS usually settles to 730 (0.5 CF). To correct my PH, I add 3-4ml of PH down, so that would be 0.3-0.4ml/Gal and that gets right to 5.8 and holds there for about 4-5 days before minor adjustment is needed.

1731822
1731823


The above charts are my most recent mixes. I am experimenting with elevated P in mid bloom, and I also bumped up N and Ca some as well. There are a few instances I had to intentionally input undesired targets into HB to trick the app to output more overall desired results. The levels of micros are far from ideal, and though I know exactly what I'd like to accomplish, achieving that with these premixed products like Peters and STEM is a lot more difficult than imagined. Ultimately, I might locate everything individually and build my own part A and call it Sky Nutes or something stupid like that, lol. As is now though, the micro mix is acceptable levels, some a tad high, others a tad low, but still better than what's in bottled nutes that I've seen.
 

Skybound

Well-Known Member
Because I mix my concentrates @ 1 gram of salt to 10ml of RO, it's stupid easy to convert the doses. What you see next to each component is the required weight of each component per gallon, so to account for the 1:10, just shift the decimal to the right one position, then multiply that by the number of gallons. In my case that's an even 10 gallons, so I'd shift the decimal right one more position. It's only a bit tricky when mixing the Veg regimen. My veg res is about 6-7 gallons, so I only target to about 4 gallons to produce a more diluted mix. So for Silica for example which is 0.383 grams per gallon, I'd shift the decimal to 3.83 and know I'd need 3.83ml per gallon, then multiply that by 4 or 5 to realize what's need.

By mixing concentrates @ 1:10, I can easily retrieve a very small dose without needing a scale as a tenth of 1 gram equates to 1ml, or a hundredth of a gram is a tenth of a ml, and when using various feeder syringes, getting a small dose is brainless. For the record, I regularly use a 3ml, 12ml, 20ml, 35ml, and a 60ml syringe. The 3ml graduates in tenths, so I can visually see 0.01 grams in liquid form.
 

Skybound

Well-Known Member
After a lot of fighting with the app to produce a reasonable range of micros using Peter's Pro as the primary source and their STEM as the secondary, I decided to invest the $70 to get all of the raw elements and build a blend that will (should) complement the Peter's and Jack's perfectly for cannabis. I'm still on the fence whether to use chelated Iron DTPA, or Iron Sulfate, but whatever I decide to try, I'll use for a while and then share that recipe and mixing instructions, and also my results. I found a good short read about chelated Iron and why it's important. Someone on another forum advised me not to mix the Iron DTPA with STEM, but he couldn't explain why or provide me a link, so I now have to research that out before I conclude what my best path forward would be, but when my order arrives, I'll have both sources of Iron on hand.

Iron Sources in Hydroponics : Which One is the Best ?
 

Skybound

Well-Known Member
From the link, it sounds like you need to use the chelated stuff. So you want to add more iron than the STEM already gives?
Yeah, but it's much more than that. My research suggests the best staring point, or possibly even finishing point in terms of ppm of each micro/trace is as follows;

Iron - 2
Manganese - 1
Zinc - 0.3
Boron - 0.3
Copper - 0.2
Molybdenum - 0.05

To the best of my knowledge, these values do not change throughout the grow, so I'm trying to get a concoction that will resolve Peter's Pro or Jack's pro to those numbers. You can see in my feed charts a few posts back how far I am from my intended targets, and in a lot of cases, I have to omit a target, or intentionally input an undesired target to trick the app to resolve in a way that I find to be the closest as possible to my total targets, which IMO is still pretty far away from where I want to be. So I am taking it to the next level and will build my own micro blend and stop using STEM all together. I will mix all of the same components that in STEM, with maybe the exception of Iron, but once I get the Part A dialed in, it becomes very easy to tweak the Macro and Secondary elements due to them all being in much higher concentrations.

For the record, my research mostly consisted of piquing the brain of a more seasoned hydro grower to nail down overall desired targets, then I cross referenced those against other people's experience and whatever the internet offers in free info which aint a lot. So I've been on a trial and error since then and already worked out like 4 minor concerns that if left unadjusted for, would've all ganged up to make less tasty bud. Well, I wish to continue to dial in the recipe and the numbers and who knows, if a few people contribute and share their findings, we could easily form a database that can show different data points like Sativa, Indica and everything between as we already know they like somewhat different diets. I primarily grow Indica leaning hybrids and have a few pure Indicas that I'm considering, so I should be able to dial that end of the spectrum in fairly close enough. Then the next grower should have a pretty accurate starting point. Of course my motivation began selfishly, but no point in keeping it all and not sharing to the community, right?
 

Skybound

Well-Known Member
I think I found what I was looking for. This suggests chelated should only be mixed with other chelated which means I'll have to use all sulfates and hunt for chelated Zn, Cu and Mn. In this same article, the author claimed success with unchelated micros, but the chelated ones have a better chance of remaining available.

The most common of these agents is called Ethylendiamintetraacetic Acid (EDTA), a tetraprotic acid which is able to chelate most metals with a particularly high afinity for Fe. However, when you add only chelated iron, the fact that other metals start to compete makes the iron complex destabilize and the chelate is eventually destroyed. However, when we add the chelating agent we can make sure that we add enough to "wrap" Fe and other metals in such a way that the stability of the iron complex is guaranteed.
Preparing your Own Chelates – Improving Your Hydroponic Nutrients
 

Skybound

Well-Known Member
I decided to discontinue using Peter's 5-11-26 b/c I didn't want to take the chance of screwing up the math when calculating how much micro mix would be needed to amend per the respective dose of the Part A. That said, I mixed up a gallon of micro mix to my desired targets, then I'll just use the components to fill out the macros and secondaries. Because I jumped the gun and ordered all sulfate micros, I will only be using this mix for a few weeks at most. I currently have Iron-DTPA on hand, but still need to acquire Zinc-EDTA, Manganese-EDTA and Copper-EDTA to make my chelated micro mix, but I will target those to the same ideal values I was able to learn from RIU (thanks for im4satori & nxsov180db). The sulfate micro mix is as follows;

Custom Micro Mix === grams per 1000 gallons
Iron || Sulfate (Hepta)---------22.743 ...............$4.75 lb
Copper Sulfate (penta)-------------2.38 ..............$10.15 lb
Boric Acid-----------------------------3.638 ...............$9.54 lb
Manganese Sulfate (Mono)------11.33 ..............$5.00 lb
Sodium Molybdate (Di)------------0.229 ..............$14.20 8oz
Zinc Sulfate (Di)--------------------02.772 ...............$5.00 lb
I mixed the above weights into 1 gallon of RO, then divided that gallon's number of ml by that thousand and concluded that I will need 3.78ml per gallon of reservoir that I rounded up to 3.8ml/Gal. My targets are as follows;

Iron = 2 PPM
Manganese = 1 PPM
Zinc = 0.3 PPM
Boron = 0.3 PPM
Copper = 0.2 PPM
Molybdenum = 0.05 PPM
To build the rest of the feed, I use;

Potassium Silicate (for silica)
Calcium Nitrate (Cal Nit)
Magnesium Nitrate (Mag Nit)
Monopotassium Phosphate (MKP)
Magnesium Sulfate (Epsom)
Potassium Sulfate (Pot Sul)

These 7 mixes allow me to hit my targets like Johnny on the Spot! So no more lying to Hydro Buddy trying to trick it to return with numbers that are the most tolerable. I should know in a few days if my math was screwed up, but I think it's good. I did all of my reservoirs with that STEM shit that oxidized so I expect some minor damage, but hopefully I'll feel safe to use the new mixes with everything next week.
 

LiberalThinker

Well-Known Member
Hello skybound. My brain hurts at the work you've put in and I salute you. :thumb: Going to your earlier post about micro-nutrient deficiencies in the GH range that you experienced. Bear in mind hydro is new to me and very much learning. Looking at an element absorption vs pH chart, it seems that there is a "hole" between the manganese and calcium absorption where you can either optimise pH for one or the other but not both. This what I'm looking at:

1742575

Would increasing the manganese part with a chelated supplement improve its absorption by the plant if you optimised the pH for calcium to 6? My thinking is that everything would be within absorption range then at 6.
 
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