Will APFUK starter kit suit my needs?? Further advice needed

EA James

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Hi all,

During lockdown i bought my first lot of dry salts, individually from Aqua plants care. Since then I've had a few minor issues caused by excess nutrients and from posts on here a few people thought my nitrates were high enough from the tap to not need to add any more.

I Haven't been dosing for around a month now and surprisingly the diatom looking algae has cleared up and the glass is staying clean in between water changes. I'm also injecting co2 so i'm quite shocked that i'm not having any issues.....BUT!... I know that its probably not going to stay like that?! Saying that I'm starting to see a bit of a difference in some of the leaves of my crypts (yellow dots) but I'm not sure on what that is but generally the tanks doing ok.

So according to my water report my minimum nitrate level is 31.6 and i think the max was around 40ppm. I was using potassium nitrate in my old recipe so firstly does the APFUK starter contain that and if so should i not add any? Or should i swap the KNO3 for something else?

Also on that note how long would it take for the nitrates in my tank to deplete? I'm guessing plant volume would play a big part in that answer so probably a stupid question?!

I'll post a pic of the tank in it's current condition so you can see the plant mass for the fert help, as always, any help will be appreciated 👍

Cheers, James
 

EA James

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X3NiTH

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APFUK salts totally fine to use.

If there is a commensurate amount of Potassium to Nitrogen in the tap water then omit the KNO3 from your dosing regime, if there’s not then you can supplement Potassium from either Potassium Chloride or Potassium Sulphate, the Carbonate or Bicarbonate of Potassium if used will increase the KH (Carbonate Hardness) of the tank water and pH will rise correspondingly.

If you are using Magnesium Sulphate as part of your macro mix (it comes in the APFUK kit along with KNO3) then I would suggest sourcing and using Potassium Chloride for the Potassium rather than the Sulphate if only to limit the total amount of Sulphate in the tank.

There’s not many limits to what you can do, nothing stopping you getting creative and using all the forms of Potassium together if you need to get specific values for everything in the water.

:)
 

EA James

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Hi @X3NiTH sorry i haven't had the time to reply to you sooner. Thank you for the reply

If there is a commensurate amount of Potassium to Nitrogen in the tap water
I don't that I'm afraid, I'm still very new the whole EI thing and science wasn't my strong point at school and still isn't now so to be honest i find it all a bit confusing! Do i need a Potassium test kit to help find the answer?

nothing stopping you getting creative
Apart from lack of knowledge 😂 I'm trying to get it to sink in so please bare with me!

Thanks again
 

dw1305

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Hi all,
Do i need a Potassium test kit to help find the answer?
No, you don't. There <"is a kit">, but it is actually quite difficult to measure <"potassium (K) levels colormetrically">, because of the <"solubility of potassium salts">.

Measurement is very straightforward with any of <"Flame Photometry, Atomic Absorption Spectrophotometry (AAS) or Inductively Coupled Plasma (ICP)"> if you have access to them.

Your water company has the right analytical kit, but there isn't a regulatory limit for potassium, so most companies don't report the value.

If you have high levels of nitrate (NO3-) in your tap water, you are also likely to have elevated levels of potassium from the same sources.

If you thought you might have low potassium levels and you didn't want to add any potassium nitrate (KNO3), then @X3NiTH's is a good suggestion
I would suggest sourcing and using potassium chloride
KCl is easy to find as "sodium free salt".

cheers Darrel
 

X3NiTH

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Natural background Potassium levels worldwide in drinking water supplies is usually somewhere between 1ppm to 5ppm, there are outliers to this of course depending on local mineralogy and agricultural pollution. Here’s what the WHO have to say about background potassium - Potassium– Background Document Revised WHO draft – March 2009

If you assume you have low levels then you can add a Potassium source to a commensurate level to that of the Nitrate and be a near or not far over 1:1 ratio of N:K if there is already 1:1 of N:K without a further salt addition then adding more is ok, a ratio of N:K where 1:>2 is not problematical, I have run 1:>5 (sourced from Potassium Bicarbonate for KH dosing) and I never saw any issue.

Add whatever is easiest!

:)
 

EA James

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If you have high levels of nitrate (NO3-) in your tap water
Minimum 31.6
Mean 35.5
Max 40.5
I'm guessing I'd work off the middle figure? Is that an adequate amount for my tank for the week?

If you assume you have low levels then you can add a Potassium source to a commensurate level to that of the Nitrate
Well from looking at potassium deficiencies on good old google today i think a few of my plants may be suffering with this. But, I haven't been dosing any ferts for about 5/6 weeks now so that could be why, not sure if they were there before. I'll take your advice and get some potassium chloride, i then use that instead of the potassium nitrate in my mix?

Thanks guys :)
 

dw1305

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Hi all,
Minimum 31.6
Mean 35.5
Max 40.5
I'm guessing I'd work off the middle figure? Is that an adequate amount for my tank for the week?
Yes, that should be plenty of NO3, even the minimum value (which will be sometime in the winter) is pretty high.
I'll take your advice and get some potassium chloride, i then use that instead of the potassium nitrate in my mix?
Yes. There is a slight difference in the % percentage pf potassium, the RAM of K is 39.1 and the RMM of KNO3 is 101 and it is 36% K. For KCl the RMM is 74.5 and it is 39.1/74.5 = 52.5% potassium.

This means that there is the same amount of potassium in 1g of KNO3 and ~0.7g of KCl.
i think a few of my plants may be suffering with this. But, I haven't been dosing any ferts for about 5/6 weeks now so that could be why,
You should get a pretty instant greening if your plants are potassium deficient. For geological reasons your tap water won't have supplied much magnesium (Mg) either, so that is another possibility for the deficiency symptoms.

cheers Darrel
 

EA James

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Thanks for the reply @dw1305 thats helped things be more clearer in my head!
These are the few deficiencies I’ve noticed and from what I’ve read online they do seem to be caused by lack of potassium and/or magnesium, would you agree?
Cheers, James
 

EA James

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@dw1305 @X3NiTH
Evening all, i need some help if would please?!

I took your advice and sourced some Potassium Chloride to replace the KNO3 for my mix, I've also replaced my previous trace elements for the APFUK trace from previous advice here on the forum.

The salts i now have in stock are-

Potassium Chloride
Monopotassium Phosphate
Magnesium Sulfate
Potassium Sulphate

So basically i'd like some help with how to mix it all up correctly, I don't know how much of each one to add. And do i need to use all four in my mix? I know there are the dosing calculators on here but i can't figure it out! Last time i used @Zeus. calculator but that was with ALOT of his guidance! I don't know how much i should dose into the tank once its mixed either, i find it so confusing!

Any help would be great

Cheers, James
 

Zeus.

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How much to dose is a tricky question to answer, as it would be nice to dose just enough to prevent waste in salts and using excessive water. The excessive use of salts can easily be compensated for by watering your garden/hose plants with old tank water. Seeing as you have you own salts I would aim for the EI/Clives dosing ppm's, then if all is growing well just reduce the dose in small 10% drops waiting 4-6 weeks and as soon as you see some plants showing deficiencies just increase the dose 10%
 

X3NiTH

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Personally I would treat the Sulphates and Chlorides as remineralisation salts to be added at water change (provided it’s a 50% change to prevent accumulation) the phosphate I would add first to a level at water change and then dosed according to EI (alternate dosing temporally from micro/iron dose). I would ratio the potassium content to total nitrate after water change to around 1:1 (excluding the K from KPhos extra ppm dosing during the week as it’s minimal). I would do 1:1 with the potassium sulphate and potassium chloride at a minimum, if I were to go further I would maybe calculate the total sulphate content of the water from the added magnesium sulphate and maybe the totals for the micro (maybe 1 or 2 ppm overall over the week) and then balance the totals to be 1:1 chloride to sulphate, it’s not essential it’s just me!

:)
 

EA James

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Seeing as you have you own salts I would aim for the EI/Clives dosing ppm's, then if all is growing well just reduce the dose in small 10% drops waiting 4-6 weeks and as soon as you see some plants showing deficiencies just increase the dose 10%
Ok that makes sense, where can i find those dosing ppm's? I remember you had them on your calculator but that's not ready yet is it?

@X3NiTH I'm really sorry but i don't understand that at all! I'm pretty much a complete beginner at the whole dry salts/ferts thing. Sorry 🤦‍♂️
 

X3NiTH

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Ok rather than try to explain the above again we can go through the workings using real numbers, to do this I need to know (in this thread to keep it all in one place) -

1. Tank Water Volume?

2. GH and KH (if you don’t know this can you find and link to your local water report, if not let us know the area you live and we can look)?

3. Would you rather add the macro (K+Mg) elements in one go at water change (remineralisation) and dose your N+P source macro every other day (Micro dosed on the alternate days as per EI) or do you want to roll it all together in one bottle for using 3 macro doses per week as per EI = Macro-Micro-Macro-Micro-Macro-DayOff?

4. Any preference as to the average level of Nitrate you want in the water if you have control of this (depends how much on average is in the tap supply whether larger amounts of N are needed)?

5. List of all the salts you have to hand?

From this we should have a good idea of what you should be dosing.
 

X3NiTH

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Okay senior moment done with, you can ignore query 4, I’m all good with having answers here to the rest of the queries though if you can (so if others stumble across this page then all the workings are here to compare/replicate).
 
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EA James

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@X3NiTH You're a star, Thank you so much 🙂

1. Tank water volume is 330 litres, Canister filter is 14 litres

2. GH and KH I'm not 100% sure on if i'm being honest. My water report has total hardness of 283ppm if that helps at all?
GH reading from an NT labs liquid test kit is 15 doh and KH was 10 doh (I know a few members don't like test kits hence the not being sure part!)
I live in Wraysbury in Berkshire just in case you need that, Water supplier is Affinity water.

3. I would prefer to dose Macro Micro on alternate days then WC as a rest day if that's ok?

4. Level of Nitrate i have no idea whats needed but on the water report my average 35.5, minimum was 31.6 and max 40.5ppm

5. Ok salts i have available at home are-

Potassium Chloride
Magnesium Sulfate
Monopotassium Phosphate
Potassium Sulphate
Potassium Nitrate
Chelated Trace elements

I answered number 4 as i think too much info is better than not enough! Anything else you need I'll send over straight away. Thanks again, i really appreciate it 👍

Cheers, James
 

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