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IFC Aquarium Fertilizer Calculator

Zeus.

Fertz Calc Meister
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1 Oct 2016
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4,352
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Yorkshire,UK
'average' n my area at time of this report (year of 2020) is 12.3mgNO3/L
Be careful with averages as they can sometimes vary greatly over the year, some elements can vary 100 fold in some water reports. For the nitrate I would use the lowest value for the year or just ignore the waters reports nitrate value, its there more for folk

We all do typos its only human ;)
 

Karmicnull

Member
Joined
6 Sep 2020
Messages
523
Location
Cambridge
Hi @Zeus, @Hanuman, I'm playing around with my fert dosing from first principles (molar masses etc.) and using your spreadsheet and APF 'EI' dosing as a reference to reconcile against However my own maths comes to a slightly different answer, and I can't unprotect the hidden stuff in the spreadsheet to reverse-engineer your calcs!

According to the 'TargetCalculator' sheet, APFUK EI starter kit is per week:
14.70 ppm NO3
4.20 ppm P04
11.00 ppm K
7.30 ppm Mg

But when I do the maths for APF UK (at 4tsp KNO3, 1tsp KH2PO4, 6tsp MGSO4-7H20) I get
19.68 ppm NO3
4.61 ppm P04
14.31 ppm K
3.56 ppm Mg

I'm pretty sure my spreadsheet is bug-free, so the only variable I can't control is: What have you used as the weights of a teaspoon? Your values are far more likely to be correct than mine! By way of comparison, after trawling the internet, I've used:

chemicalweight of one TSP (g)
KNO36.8
KH2PO45.6
K2SO4 (not used in APF kit)6.4
MGSO4 - 7H205.1

Cheers,

Simon
 

Zeus.

Fertz Calc Meister
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Location
Yorkshire,UK
Hi Simon,

Thanks for pointing out your findings. I will have a look at it over the next few days. The calculations for APFUK teaspoons was done a long time ago so I can't remember off the top of my head what mass for teaspoons was used, so will need to find the which version the calculation was on, as the present version just states the ppm yields. We decided not to use spoons as a form of measurement as the mass per spoon can vary dependant on the grain size of the salt. Not the the variation in mass would make much difference as long as the salts are in abundance.
Mistakes/errors/oversights happen even when you think you have it right ;)

Cheers,
Zeus
 

Karmicnull

Member
Joined
6 Sep 2020
Messages
523
Location
Cambridge
I will have a look at it over the next few days. The calculations for APFUK teaspoons was done a long time ago so I can't remember off the top of my head what mass for teaspoons was used, so will need to find the which version the calculation was on, as the present version just states the ppm yields. We decided not to use spoons as a form of measurement as the mass per spoon can vary dependant on the grain size of the salt.
Thanks Zeus, much appreciated. I agree wholeheartedly with your decision on teaspoon accuracy - I can see why so many Scapers have precision scales; they're definitely on my list. Mind you it's getting to be a pretty long list. :eek:

Cheers,
Simon
 

Zeus.

Fertz Calc Meister
Joined
1 Oct 2016
Messages
4,352
Location
Yorkshire,UK
Had a think about it today and thought don't mess about its not rocket science :rolleyes: ,weight some salts x10 teaspoons, two scales, and weight it three times on two different scales take average
1622840373039.png


So weighed the mass of a little plastic tray first, could of used 'tare' but thought it best to allow for scales turning off in the process- which they did
1622840485310.png

The KNO3, KH2PO4 and Trace was from APFUK and the Epsom salts was from Ebay, all packages/bags have been open for some time and the Trace was a little lumpy.
So based on my average weight per teaspoon
1622842712744.png


Based on the quoted masses you have

1622842112504.png

So much depends on the actual weight per teaspoon of the salts being sold when freshly open. But the basic husbandry of plants remain the same - watch them and they will tell you if there isn't enough (or too much) of anything.

But yes we was wrong in the valves for the APFUK fert valves :oops:, which is a little embarrassing after all the time and effort we spent. How we got it wrong 🤷‍♂️ ATM

We could do with some verification of some other members mass off each salt/trace from freshly opened bags IMO, ten teaspoons and take average and we will update the calculator ASAP ;)
 

Karmicnull

Member
Joined
6 Sep 2020
Messages
523
Location
Cambridge
e could do with some verification of some other members mass off each salt/trace from freshly opened bags IMO, ten teaspoons and take average and we will update the calculator ASAP
I feel like a right numpty now. I spent flipping ages surfing the net trying to find out what different salts weighed per teaspoon rather than doing this. I'll do this tomorrow and give you your first measured reading. :banghead:
 

Hanuman

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Thread starter
Joined
4 Jan 2019
Messages
690
Location
Thailand
But yes we was wrong in the valves for the APFUK fert valves :oops:,
Where are the values wrong?

a little embarrassing after all the time and effort we spent. How we got it wrong 🤷‍♂️ ATM
I am not embarrassed a single bit since weight of a tsp is dependent of the freshness of the product, if the tsp is flush or not, how finely the compound is grind, air humidity %, grain spacing, is it compacted? etc...So many variables. You see where I am going.
Not even sure of the necessity to update the calculator for this considering that someone else might come saying that a tsp of KNO3 is not 6.8 but 6.5 or 5.9. And he will be right.
Your weighing clearly also differs from the one of Karmicnull.
Here is another example: Teaspoons to Grams conversion via Chemical density
I also made some weighing with my teaspoon/scale. I didn't even bother doing a double weighing with my lab grade scale because the next folk coming will say yet different numbers. My results:
1622875568184.png


What is important to keep in mind is that we are already in the "over dosing" territory when doing EI so a little more or a little less won't make much of a difference if any.
 

Karmicnull

Member
Joined
6 Sep 2020
Messages
523
Location
Cambridge
My measurements this morning added in (for approx 8 month old APFUK packets) - I did 20 tsp rather than 10 as my scales are lower granularity.
1622885510292.png

As Hanuman predicted there is variance (up to 10%) which is probably trivial given the EI overdosing philosophy. Perhaps it matters more for those who lean dose.

Cheers,
Simon
 

Hanuman

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Thread starter
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4 Jan 2019
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690
Location
Thailand
Small note:
what I used was not APFUK products. What I have are generic compounds that I bought locally which are probably close to two years old but it's all the same as what APFUK sells are raw unadulterated compounds so basically the same thing here or on the other side of the earth.
 
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Wookii

Member
Joined
13 Nov 2019
Messages
2,579
Location
Nottingham
Hey @Zeus. / @Hanuman - is the Remineralisation section part of the downloadable calculator as yet, I can't seem to find it?

EDIT: Scratch that, found it in the DIY section under the first drop down menu 👍

EDIT 2: Nope, that's not the section I was looking for, where is this screen @Zeus.:

1620147526294-png.png
 
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Zeus.

Fertz Calc Meister
Joined
1 Oct 2016
Messages
4,352
Location
Yorkshire,UK
Hey @Zeus. / @Hanuman - is the Remineralisation section part of the downloadable calculator as yet, I can't seem to find it?

EDIT: Scratch that, found it in the DIY section under the first drop down menu 👍

I have done a new Remineralisation sheet which is about 95% done on my side which I believe is more comprehensive, however due to myself and Hani being very busy it will be some time before its released
1624527452750.png

1624527499159.png

I've even added sodium bicarb and sodium carbonate which has been handy in comparing some of the commercial remin agents, although these two salt will be hidden on release or have an extra tick box to active them, as I feel there is no need to use the salts in our tanks and keep the [Na] down.
It even does remin solutions
 

Wookii

Member
Joined
13 Nov 2019
Messages
2,579
Location
Nottingham
I have done a new Remineralisation sheet which is about 95% done on my side which I believe is more comprehensive, however due to myself and Hani being very busy it will be some time before its released
View attachment 171136
View attachment 171137
I've even added sodium bicarb and sodium carbonate which has been handy in comparing some of the commercial remin agents, although these two salt will be hidden on release or have an extra tick box to active them, as I feel there is no need to use the salts in our tanks and keep the [Na] down.
It even does remin solutions

Thanks, that's what I was looing for, my Edit 2 crossed with your post.

Yeah, whilst I don't really want to be adding Sodium Bicarb, I note using Potassium Carb/Bicarb always pushes the K well above target. I know technically this shouldn't matter, but still . . .
 

dw1305

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UKAPS Team
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7 Apr 2008
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nr Bath
Hi all,
I note using Potassium Carb/Bicarb always pushes the K well above target.
<"It does">. Personally I'd still rather use KHCO3 than NaHCO3.

If you were bothered about the potassium content, you would need to use urea (CO(NH2)2) as your <"nitrogen source">, rather than potassium nitrate (KNO3).

cheers Darrel
 
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Wookii

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Location
Nottingham
Hi all,

<"It does">. Personally I'd still rather use KHCO3 than NHCO3.

If you were bothered about the potassium content, you would need to use urea (CO(NH2)2) as your <"nitrogen source">, rather than potassium nitrate (KNO3).

cheers Darrel

Thanks Darrel, yeah I don't really want to mess with Urea, a bit too risky.

I did wonder about using Magnesium Nitrate instead of Potassium Nitrate, but the only places I can seem to find it for sale are charging £50 for 10 grams - unless I'm looking up the wrong variant.
 

dw1305

Expert
UKAPS Team
Joined
7 Apr 2008
Messages
13,110
Location
nr Bath
Hi all,
I did wonder about using Magnesium Nitrate instead of Potassium Nitrate, but the only places I can seem to find it for sale are charging £50 for 10 grams - unless I'm looking up the wrong variant.
Magnesium nitrate would be an option, you should be able to find the hexahydrate (MgNO3.6H2O) pretty cheaply in "fertiliser grade".

This one is £12 a kilo <"Nova Mag-N 11-0-0+15.5MgO ( magnesium nitrate ) 1 KILO">.

cheers Darrel
 

erwin123

Member
Joined
4 Mar 2021
Messages
577
Location
Singapore
As I have a single 60cm tank, roughly 100 litres, I'm still ok with the cost of all-in-ones ferts though I have been researching which is the most 'cost effective one available' so I'm using the spreadsheet for that purpose rather than to calculate how to DIY... Currently I'm on APT Complete but looking to convert to APT EI

I noticed that the IFC Fert Calculator includes APT Complete but not APT EI. APT EI is the same price as APT Complete.

If I convert the APT Complete numbers to APT EI , I get:

APT EI
21ml /100l/week
15.33 ppm NO3
6.43 ppm PO4
22.37 ppm K
8 ppm Mg
0.52 ppm Fe

And I hope I'm doing it correctly, but if I convert the TNC Complete to 100l at 20ml a week and Tropica to 24ml a week to closely approximate the APT EI dosage of 21ml I get:
TNC Complete
20ml/ 100l/ week
13.28 ppm NO3
1.32 ppm PO4
10 ppm K
0.16ppm Mg
0.16 ppm FE

Tropica Specialised
24ml/100l/ week
14.24 ppm NO3
0.74 ppm PO4
2.48 ppm K
0.94 ppm Mg
0.16 ppm FE

I apologise in advance if I misunderstood the spreadsheet and my calculations are wrong. But based on these numbers I could live with the cost of dosing 3ml of APT EI a day.
 
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