• You are viewing the forum as a Guest, please login (you can use your Facebook, Twitter, Google or Microsoft account to login) or register using this link: Log in or Sign Up
  • You can now follow UKAPS on Instagram.

Mixing dry macros

Larix83

New Member
Thread starter
Joined
22 Feb 2022
Messages
12
Location
RSA
hi there

so i ordered my dry ferts and they arrived. i have a 500 litre tank. i am a bit confused, some articles have recipes including MgSO4 and others only add KNO3 and KH2PO4. others even include KCl. please help, how do i mix the macro solution for my tank.
Using this article these are my calcs when using a 2l dosing bottle and the rotalabutterfly calculator.
If dosed daily:

Nitrate (NO3) 20ppm per week. 20/7 = 3ppm

Potassium (K) 30ppm per week. 30/7=4ppm
Phosphate (PO4) 3ppm per week 3/7= 0.5ppm
Magnesium (Mg) 10ppm per week 10/3=1.5ppm

260.88 grams of KNO3 to your 2000mL dosing container. Add 20mL of that mix to your 500L aquarium daily = 3.2ppm NO3; 2.02ppm K

42.99 grams
of KH2PO4 to your 2000mL dosing container. Add 20mL of that mix to your 500L aquarium daily = 0.6ppm PO4; 0.25ppm K

164.93 grams
KCl to your 2000mL dosing container. Add 20mL of that mix to your 500L aquarium daily

= 1.73ppm K

1,014.09 grams
of MgSO4.7H2O to your 2000mL dosing container. Add 20mL of that mix to your 500L aquarium daily = 2ppm Mg
 
Solution
Nitrate (NO3) 20ppm per week. 20/7 = 3ppm
Potassium (K) 30ppm per week. 30/7=4ppm
Phosphate (PO4) 3ppm per week 3/7= 0.5ppm
Magnesium (Mg) 10ppm per week 10/3=1.5ppm
If I use your ppm weekly targets you would need the following amounts (look at the container column):
1646062207597.png


Instead, this is what you would get in terms of ppm values if you dosed those amounts (look at the "GRAN TOTAL PPM" line):
260.88 grams of KNO3 to your 2000mL dosing container. Add 20mL of that mix to your 500L aquarium daily = 3.2ppm NO3; 2.02ppm K

42.99 grams
of KH2PO4 to your 2000mL dosing container. Add 20mL of that mix to your 500L aquarium daily = 0.6ppm PO4; 0.25ppm K

164.93 grams
KCl to your 2000mL dosing container...

dw1305

Expert
UKAPS Team
Joined
7 Apr 2008
Messages
14,005
Location
nr Bath
Hi all,
260.88 grams of KNO3 to your 2000mL dosing container. Add 20mL of that mix to your 500L aquarium daily = 3.2ppm NO3; 2.02ppm K

42.99 grams
of KH2PO4 to your 2000mL dosing container. Add 20mL of that mix to your 500L aquarium daily = 0.6ppm PO4; 0.25ppm K

164.93 grams
KCl to your 2000mL dosing container. Add 20mL of that mix to your 500L aquarium daily

= 1.73ppm K

1,014.09 grams
of MgSO4.7H2O to your 2000mL dosing container. Add 20mL of that mix to your 500L aquarium daily = 2ppm Mg
Run them through the IFC calculator, I'd guess <"you've exceeded the solubility limit">.
some articles have recipes including MgSO4
It will always be the heptahydrate in use (which you've written), and 10% magnesium. Some USA based recipes leave magnesium (Mg) out altogether, because much of their ground water contains magnesium for <"geological reasons">. I'm not sure about in S. Africa.
add KNO3 and KH2PO4. others even include KCl
It doesn't matter where the potassium (K+) ion comes from, they are all the same in solution. You get more K (51%) with KCl, than you do with KNO3 (29%) or KH2PO4 (29%).

The advantage of potassium dihydrogen phosphate (KH2PO4) and potassium nitrate, over potassium chloride (KCl), is that the anion is also a plant nutrient, PO4--- and NO3-.

cheers Darrel
 

Hanuman

Member
Joined
4 Jan 2019
Messages
1,464
Location
Thailand
Nitrate (NO3) 20ppm per week. 20/7 = 3ppm
Potassium (K) 30ppm per week. 30/7=4ppm
Phosphate (PO4) 3ppm per week 3/7= 0.5ppm
Magnesium (Mg) 10ppm per week 10/3=1.5ppm
If I use your ppm weekly targets you would need the following amounts (look at the container column):
1646062207597.png


Instead, this is what you would get in terms of ppm values if you dosed those amounts (look at the "GRAN TOTAL PPM" line):
260.88 grams of KNO3 to your 2000mL dosing container. Add 20mL of that mix to your 500L aquarium daily = 3.2ppm NO3; 2.02ppm K

42.99 grams
of KH2PO4 to your 2000mL dosing container. Add 20mL of that mix to your 500L aquarium daily = 0.6ppm PO4; 0.25ppm K

164.93 grams
KCl to your 2000mL dosing container. Add 20mL of that mix to your 500L aquarium daily = 1.73ppm K

1,014.09 grams
of MgSO4.7H2O to your 2000mL dosing container. Add 20mL of that mix to your 500L aquarium daily = 2ppm Mg
1646062119524.png


The advantage of potassium dihydrogen phosphate (KH2PO4) and potassium nitrate, over potassium chloride (KCl), is that the anion is also a plant nutrient, PO4--- and NO3-.
At current NO3, PO4 and K targets unfortunately I think he doesn't have much of a choice. KH2PO4 and KNO3 do not provide enough K.
 
Solution

Larix83

New Member
Thread starter
Joined
22 Feb 2022
Messages
12
Location
RSA
just one question, the added cl and so4, do i need to worry about the cl and so4 thats now also in the water? or they safe?
 

Hanuman

Member
Joined
4 Jan 2019
Messages
1,464
Location
Thailand
so can i use this calc to mix my own micronutrients for the same tank?
My opinion about this is that if you don't have a fair amount of tanks and you are just starting to test stuff don't go crazy on spending money on chemicals etc. Darrel above made a very good suggestion about using premix micros. This at least enables you to put a foot in the DIY world without going crazy. Most of the times all these traces are sold in the 500gr/1kg packages (at least where I live) which means you would need to invest some money first. They are not that expensive but when you add everything up it might be more money than you are willing to pay for fertilizers. There is always an initial investment even in DIY.

also the ascorbic acid and the potassium sorbate, i presume preservatives?
Ascorbic acid = acidifier
Potassium sorbate = mold inhibitor.
 
Top