DIY Fertilizer Formula Recommendation

Hanuman

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Hello everyone.

I have posted this in a facebook group but it doesn't seem to be going anywhere.

I am tired of paying outrageous prices for liquid fertilizers so I though of making my own with dry salts. I know, there is a ton of info out there and believe me I have been scavenging the internet for the past week in search of a formula that suits me. I read many websites and forums and tried a few calculators. Tom Barr has been extremely insightful with all the information he has posted through the years so thanks to him for that. This said, chemistry not being my specialty all this is giving me more headaches than I wish it had and there seems to be many different opinions out there of what is good and bad.

Anyway I came across Jame's Planted Tank reformulations of TPN+ (http://www.theplantedtank.co.uk/allinone.htm) but also a few others here and there. Initially I thought I would import only the CSM+B and go from there since I already have all other dry ferts. But then I got the quote for importing CSM+B so I decided against it. So I moved on and I also came across the APT Complete made by Xiaozhuang Wong (Dennis Wong) which is basically something I would like to recreate. Perhaps if I was in Singapore I would buy it but being in Thailand it just makes it pricy to import. He does mention the ppm for each macro so I was more-less able to reverse engineer the weight of each chemical with a calculator (https://eketjall.se/akvariekalkylatorn/). However he does not give details about micros ppm (secret receipe I guess). He says he does not use CSM+B as it is trash. Tom Barr seem to think differently. See, even experts don't agree :( so it makes me even more confused.

Anyway, I just checked my stock of dry ferts and lo and behold I have all individual chemicals, including micros/trace elements! Only thing missing now is a good recipe. Here is the list of individual chemicals I have in my possession:
  • Calcium Nitrate (Ca 15%, N 15.5%)
  • Iron DTPA (Fe-DTPA 7%)
  • Iron EDTA (Fe-EDTA 13.5%)
  • Potassium Nitrate (13-0-46)
  • Magnesium Sulphate (Mg 9.35%)
  • Monopotassium Phosphate (0-52-34)
  • Monoammonium Phosphate (12-60-0)
  • Potassium Sulphate (0-0-50)
  • Manganese EDTA (Mn-EDTA 13%)
  • Boron (B 20.9%)
  • Zinc Chelate (Zn 14%)
  • Sodium Molybdate (Mo 39.5%)
  • Copper Chelate (Cu 14%)
So here go my questions:

- Are all these chemical suitable to produce a liquid fertilizer?

- If yes can anyone provide a complete formula approaching the one of the APT Complete of Dennis Wong (or something in the same vein)?

My considerations are:
- Reduce fertilisation to once a week, if possible. If not then the least possible of times per week;
- Make a all-in-one fertilization liquid;
- I have some empty 500ml bottles delivering 2ml per pump that I could use;
- I have 3 tanks. 90cm, 60cm, 36cm. All pretty much heavy planted. The 60 is only composed of bucephalandra;

If a kind hearted, experienced wizard ‍♂could help me out creating a formula that can fit the above it would be highly appreciated. Thank you.
 

dw1305

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Hi all,
Here is the list of individual chemicals I have in my possession:
  • Calcium Nitrate (Ca 15%, N 15.5%)
  • Iron DTPA (Fe-DTPA 7%)
  • Iron EDTA (Fe-EDTA 13.5%)
  • Potassium Nitrate (13-0-46)
  • Magnesium Sulphate (Mg 9.35%)
  • Monopotassium Phosphate (0-52-34)
  • Monoammonium Phosphate (12-60-0)
  • Potassium Sulphate (0-0-50)
  • Manganese EDTA (Mn-EDTA 13%)
  • Boron (B 20.9%)
  • Zinc Chelate (Zn 14%)
  • Sodium Molybdate (Mo 39.5%)
  • Copper Chelate (Cu 14%)
So here go my questions:

- Are all these chemical suitable to produce a liquid fertilizer?
They are all soluble, so the answer is "yes". Once a salt has dissolved into ions, every K+ ion is the same as every other K+ ion, it doesn't matter which compound they came from. We use compounds like potassium nitrate (KNO3) because you get more "bang for your buck", both the anion (NO3-) and the cation (K+) are macro-nutrients.

You could make an "all in one", you would need to acidify it with a weak acid, citric or acetic acid etc.

Have a look at <"James Planted Tank">, that gives you the breakdown of various commercial "all in one" formulations.

If you use the monoammonium phosphate (NH4H2PO4) you need to be aware that the ammonia/ammonium is toxic to livestock at fairly low levels, but you can leave it out and use the other compounds to supply both PO4--- and N (as the non-toxic NO3).

You'll also need to convert the N-P-K values for the fertilisers to % element. The formulae to do that are in <"percentage.....">, if you read to the end of the page it has a couple of worked examples.

The other thing is that the MgSO4 is the <"heptahydrate (MgSO4.7H2O)">, which is why it is ~10% Mg, calcium nitrate is the tetrahydrate etc.

cheers Darrel
 

Hanuman

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Have a look at <"James Planted Tank">, that gives you the breakdown of various commercial "all in one" formulations.
Thanks Darrel. Appreciate the input. Yes that's the one I wanted to give a shot initially but he uses the CSM+B which is pricy to import here.

You'll also need to convert the N-P-K values for the fertilisers to % element. The formulae to do that are in <"percentage.....">, if you read to the end of the page it has a couple of worked examples.
Meaning I can find out the weight of the trace elements by looking at the % of the DIY TPN+ (3) ?
 
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dw1305

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Hi all,
Yes that's the one I wanted to give a shot initially but he uses the CSM+B which is pricy to import here.
I've just seen your <"other post">, and I'd just use the "NIC- Spray trace element solution". As @Zeus. says it doesn't contain absolutely everything, but the nutrients plants need as really trace trace elements are unlikely to cause deficiency (basically "any at all" is enough).
Meaning I can find out the weight of the trace elements by looking at the % of the DIY TPN+ (3) ?
Yes.

cheers Darrel
 

Hanuman

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As @Zeus. says it doesn't contain absolutely everything, but the nutrients plants need as really trace trace elements are unlikely to cause deficiency (basically "any at all" is enough). Yes.
cheers Darrel
Actually it does contain Nickel. I asked the reseller of the product to send me the certificate of analysis from the actual producer. I just received it a few minutes ago. The reason why the reseller don't add the nickel content to the packaging of NIC-SPRAY is because they have to send samples of the product for analysis by government laboratories and for some reason they did not detect nickel. Perhaps old hardware? lol

Here is the certificate:
S__14630938.jpg
 
Last edited:

Zeus.

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My comment about No Nickel was more of an observation as the trace elements which are quoted on APFUK is ( their website is down ATM due to hols but I have a copy)

upload_2019-7-11_12-38-10.png


which has no Ni in according to the data sudofed give them.

So I based my custom DIY trace mix on the percentages when doing my Fe DTPA/EDDHA mix, so havnet added Ni myself either to my trace mix...........
 

Zeus.

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Just checked my water company for its water report and water has 20μg Ni/l which by my rough calculations results in a higher Ni ppm than if it was in the Micro ferts :D
 

dw1305

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Hi all,
Isn't the copper content in the nic-spray too high for fish/shrimp?
Yes it is quite high. Because it is a chelate not all of that copper (Cu) will become immediately available.

I wouldn't use it as your primary iron (Fe) or magnesium (Mg), source for that reason. You already have iron and magnesium covered with the MgSO4.7H2O and FeDTPA/FeEDTA.

You only need a trace of the other micro-elements, so I'd aim for a "safe" copper dose from the NIC spray. The actual level of safe is going to depend on all sorts of variables, soft water would make copper more available, tannic and humic substances would chelate copper and make it available over a much longer time period.

I'm not interested in optimal plant growth, so I'm happy to trade some nutrient deficiencies for lower risk.

cheers Darrel
 

Hanuman

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Ok so what about using the individual chemicals that I have instead of the nic-spray. Wouldn't that be better?
 

Hanuman

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Looking at Jame's Planted tank I would need the following chems. I was also able to calculate the % element. Correct me if I am wrong please.
Screen Shot 2019-07-15 at 16.24.27.jpg

What I am unsure is how to reverse all the % of the DIY TPN+ (3) to weights considering Jame's NPK% might not be the same as mine specially the trace elements as he using a premix (CSM+B). His formula states:

DIY TPN+ (3)
  • 48g Potassium Nitrate
  • 2.2g Monopotassium Phosphate
  • 17g Magnesium Sulphate Heptahydrate (Epsom Salts)
  • 0.5g E300 Ascorbic Acid
  • 0.2g E202 Potassium Sorbate
  • 5g EDTA Chelated Trace Elements Mix (TNC Trace, CSM+B)
  • 500ml distilled water
Screen Shot 2019-07-15 at 16.27.51.jpg


Could you help me figure that out so I can just go and weight the chemical in the scale?

Sorry if all this seems so basic for you but all these conversions are making my head turn and I just don't want to be making wild guesses or stupid mistakes and then ending up killing all the fish and shrimps.

Thank a lot Darell for all the help provided so far.
 

dw1305

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Hi all,
Ok so what about using the individual chemicals that I have instead of the nic-spray. Wouldn't that be better?
It would, you might find it is quite time consuming. I used to make up my own trace element solutions for lab. work etc.

Because you are going to be dealing with really small weights of compound, I would use <"serial dilution"> to reduce the errors in weighing., and then only add the separate micro-element solutions together (into the composite solution) right at the end. You would need to take into account the volume of the final storage vessel when you work out the ppm of nutrient supplied.

Serial dilution means you either end up with a very large volume of micro-element solution, or you are going to throw most of it away. Even if you pour most of the solutions you've made up away, it will still end up cheaper than buying a ready diluted trace mix.

cheers Darrel
 

dw1305

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Hi all,
I was also able to calculate the % element. Correct me if I am wrong please.
<"You are right">. It is only the P and K that are expressed as oxides, everything else is as percentage of the element.
What I am unsure is how to reverse all the % of the DIY TPN+ (3) to weights considering James' NPK% might not be the same as mine specially the trace elements as he using a premix (CSM+B).
Have a look at <"24hr Aquarist....">. I use a spreadsheet with a periodic table, but <"Chemical Tools"> does the same job.

Personally I'd make them up as three separate solutions. You can always combine a small volume of these (one months worth?) into an "all in one". I would use the <"Duckweed Index"> as an indication of when more fertiliser was required, but you could use a regular addition and then tailor your water changes, so that you don't get continually rising conductivity.

Solution 1: Macro-nutrients and magnesium.
Solution 2: Iron chelates.
Solution 3: Trace elements.

For "Solution 1" I'd aim for 20 ppm NO3 and K, 5 ppm P, 2 ppm Mg in the tank. You can use the <"Rotala Butterfly"> calculator for these.
For "Solution 2" I'd aim for 0.5 ppm Fe in the tank.

For "Solution 3". I wouldn't get too bogged down in trying to find the <"perfect trace element mix">. Just choose one of the trace mixes you like from <"James' Planted Tank - Comparison of traces..." > (below) and replicate that. You've already got iron and magnesium, so you don't need to add them to the micro-element mix.

Micro_element.JPG
James says - Solutions

The Haack Micro+ and Micro+ ProFe traces come in a concentrate and are diluted as directed 25ml in 500ml water.
The TNC Trace, Chempak and CSM+B traces come in powder form and have been made into a solution by adding 3g of trace to 250ml of water.
Have a look at the <"linked thread"> as well.

It is exactly this process for any element, the only difference for the trace elements is that the weights would be really small, which is why I suggest making up a stronger solution initially and then diluting it.
Stock solution
If you don't want to dose with dry salts you can make up a stock solution. In this case I've dissolved 100g of KH2PO4 in 1000 mL (1 litre) of water as my stock solution and then I've dosed 10 mL of this stock solution into my 100 litre tank, which has added ~7ppm PO4--- and ~3ppm K+.

If I wanted 5ppm PO4--- it is 7.16mL of my stock solution, or easier to do 71.6g of KH2PO4 in one litre as the stock solution and a 10cm3 dose. In both cases you would add 2ppm K+ as well.
cheers Darrel
 

dw1305

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Hi all,
Weekly dose in tank
Yes.

Because I don't dose regularly, they are just best guess, "ball-park", figures.

The advantages of dry salts and "DIY" mixes is that you can tailor your dosing to you own specific requirements. Have a look at @HiNtZ, @Zeus. and @X3NiTH posts in <"Can zinc.....">. Compared to the other people mentioned I'm a pretty shoddy aquarist, so I tend to use the <"sprinkle a bit in"> method.

Having said that this is going to sound ridiculous but I use a <"risk management"> approach to aquarium management. I don't think that the <"amount of fertiliser"> I add to the tank is really that critical, as long as I don't go mad with something containing <"urea"> or <"ammonia">.

As long as I have:
  • a reasonable plant mass,
  • including some plants with the aerial advantage,
  • and those plants are in, at least minimal, growth
I'm happy, and so are the livestock.

cheers Darrel
 

HiNtZ

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Hi all,Yes.

Because I don't dose regularly, they are just best guess, "ball-park", figures.

The advantages of dry salts and "DIY" mixes is that you can tailor your dosing to you own specific requirements. Have a look at @HiNtZ, @Zeus. and @X3NiTH posts in <"Can zinc.....">. Compared to the other people mentioned I'm a pretty shoddy aquarist, so I tend to use the <"sprinkle a bit in"> method.

Having said that this is going to sound ridiculous but I use a <"risk management"> approach to aquarium management. I don't think that the <"amount of fertiliser"> I add to the tank is really that critical, as long as I don't go mad with something containing <"urea"> or <"ammonia">.

As long as I have:
  • a reasonable plant mass,
  • including some plants with the aerial advantage,
  • and those plants are in, at least minimal, growth
I'm happy, and so are the livestock.

cheers Darrel
Despite what we discussed in those threads (including https://www.ukaps.org/forum/threads/reconstituters.55797/) I'm still chasing the dream.

I'm pretty worried that the day I find the perfect balance, I'll have nothing to do!!

With all those salts you're going to want a decent calculator, I would not recommend anything more highly than Zorfox's calc. It installs straight onto the PC. Plenty of other tools built in too.

Without it I think I would be pretty lost - only compound missing from the list that I use is MgCO3 but I know the weights > ppm by heart now so it's a minor.
 

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