Help with Using chemical fertilisers

[Big_Bill]

Hi

I've found a supplier here in the UK who sell KNO3, KH2PO4, K2SO4, MgSO4, K2CO3, CaSO4 and FeSO4.

Here is what say claim about each of these:



Potassium Nitrate
Potassium Nitrate (KNO3) contains 13.9% nitrogen (N) and 38.7% potassium (K)
Both nitrogen and potassium are macronutrients – essential for healthy plant growth.

Potassium nitrate can be added directly to a planted aquarium, or it can be mixed with water (preferably RO or DI) to make a stock solution. It can be mixed with other nutrients to make a bespoke fertilizer

If using the EI dosing system, typical maximum weekly uptake figures might be:-
Nitrogen (N) 4.5ppm. Potassium (K) 30ppm

Dry dosing
Adding potassium nitrate at the rate of 0.011 grams per litre to a tank will increase the nitrogen (N) level by
1.5 ppm and the potassium (K) level by 4.3ppm.
Added 3 times per week levels will increase by:-
Nitrogen (N) 4.5ppm.
Potassium (K) 13ppm.

Stock solution
Adding 61g of potassium nitrate to 0.5 ltr of water will give a stock solution with the following analysis:-
1.5% N (6.7% NO3) W/W
5.0% K2O (4.2% K) W/W

Added to the tank at the rate of 1ml / 10 ltr 3 x week will add 4.5ppm N and 13 ppm K




Monopotassium Phosphate
Monopotassium phosphate (KH2PO4) contains 22.8% phosphorous (P) and 28.7% potassium (K)
Both phosphorous and potassium are macronutrients.


Monopotassium phosphate can be added directly to a planted aquarium but as phosphates are normally required in very small quantities it is easier to mix it with water (preferably RO or DI) to make a stock solution.
It can also be blended with other nutrients to make a bespoke fertilizer.

If using the EI dosing system typical Maximum weekly uptake figures might be:-
Phosphorous (P) 1ppm. Potassium (K) 30ppm

Dry dosing
Adding Monopotassium phosphate at the rate of 0.0015grms per litre to a tank will increase the phosphorous (P) level by 0.34ppm and the potassium (K) level by 0.43ppm.
Added 3 times per week levels will increase by:-
Phosphorous (P) 1 ppm
Potassium (K) 1.3 ppm

Stock solution
Adding 15g of Monopotassium phosphate to 1 ltr of water will give a stock solution with the following analysis:-
0.77% P2O5 (0.34%P, 1.03% PO4) W/W
0.51% K2O (0.42% K) W/W

Added to the tank at the rate of 1ml / 10 ltr 3 x week will add 1ppm P and 1.3 ppm K.



Potassium Sulphate
Potassium sulphate (K2SO4) contains 44.9% potassium (K)
Potassium is a macronutrient – essential for healthy plant growth

Potassium sulphate can be added directly to a planted aquarium, or it can be mixed with water (preferably RO or DI) to make a stock solution. It can also be mixed with other nutrients to make a bespoke fertilizer

If using the EI dosing system typical Maximum weekly uptake figures might be:-
Potassium (K) 30ppm

Note! 13 ppm may have been provided from potassium nitrate and 1.3 ppm from potassium phosphate so only an additional 15 ppm is required.


Dry dosing
Adding potassium sulphate at the rate of 0.011grms per litre to a tank will increase the potassium (K) level by 5ppm.
Added 3 times per week levels will increase by:-
Potassium (K) 15 ppm

Stock solution
Adding 9g of potassium sulphate to 1 ltr of water will give a stock solution with the following analysis:-
0.48% K2O (0.4% K) W/W
0.16% S

Added to the tank at the rate of 1ml / 10 ltr 3 x week will add 15ppm.



Magnesium Sulphate
Magnesium sulphate (MgSO4) is used to provide magnesium an essential macronutrient.
Magnesium sulphate contains 9.86% magnesium (Mg)

Magnesium sulphate can be added directly to a planted aquarium, or it can be mixed with water (preferably RO or DI) to make a stock solution. It can also be mixed with other nutrients to make a bespoke fertilizer

If using the EI dosing system typical Maximum weekly uptake figures might be:-
Magnesium (Mg) 10ppm

Dry dosing
Adding magnesium sulphate at the rate of 0.05g per litre to a tank will increase the magnesium (Mg) level by 5ppm.
Added twice weekly, levels will increase by:-
Magnesium (Mg) 10ppm

Stock solution
Adding 56g of magnesium sulphate to 500ml of water will give a stock solution with the following analysis:-
1.0% Mg W/W
1.31% S W/W

Added to the tank at the rate of 1ml / 10 ltr 3 x week will add 3ppm.



Potassium Carbonate
Potassium Carbonate (K2CO3) contains 56.58% potassium (K)

Potassium carbonate can be added directly to a planted aquarium, or it can be mixed with water (preferably RO or DI) to make a stock solution. It can be mixed with other nutrients to make a bespoke fertilizer

If using the EI dosing system, typical maximum weekly uptake figures might be:-
Potassium (K) 30ppm

Dry dosing
Adding potassium carbonate at the rate of 0.011 grams per litre to a tank will increase the potassium (K) level by 6 ppm.
Added 3 times per week levels will increase by:-
Potassium (K) 18ppm.

Stock solution
Adding 80g of potassium carbonate to 1 ltr of water will give a stock solution with the following analysis:-

5.0% K2O (4.2% K) W/W

Added to the tank at the rate of 1ml / 10 ltr 3 x week will add 13 ppm K.



Calcium Sulphate
Calcium sulphate (CaSO4) contains 23.3% calcium (Ca)

Dry dosing
Adding calcium sulphate at the rate of 0.043g per litre to a tank will increase the calcium (Ca) level by 10ppm.

Stock solution
Adding 83g of calcium sulphate to 500ml of water will give a stock solution with the following analysis:-
3.3% Ca W/W
2.7% S W/W



Iron Sulphate
Iron sulphate (FeSO4) contains 20% Iron (Fe) which is a micronutrient.

In a planted aquarium, the target level for this element might be 0.1 ppm.
As this is small amount it is best added from a stock solution:-

Stock solution
Adding 5g of ferrous sulphate to 1 ltr of water will give a stock solution with the following analysis:-
0.1% Fe W/W
0.06% S W/W

Added to the tank at the rate of 1ml / 10 ltr will increase the iron content by 0.1ppm


Is it necessary to dose with all of these and is this the proper form of Fe to use?

Many Thanks

Bill

 

[Tom Barr]

I do not think anyone can say what a target Fe ppm is.............you can guess, but there's no consensus, never has been.

I've seen several research studies(not mere anecdotal comments) that conclude 3-6ppm of Fe is optimal for max growth..........
I add a fair amount, sometimes hitting in the 0.5-0.7ppm range.

It depends on what the light is(how many watts/liter?), the other nutrients in the tap(like NO3 etc).

In general, all the EI dosing routines are safe and easy, you can modify and tweak from there. You are starting at the high non limiting level, then you can reduce(or not, up to you here) slowly and progressively till you hit a negatibve growth and then bump back up to the next higher level.

Pretty easy to do.

Some suggest leaner dosing, then add progressively more, but this starts with limited levels and plants that are starving/limited.
I think to get a better view, you need a non limited plant that's growing well.
Then reduce from there.

I add 4 things:

KNO3
KH2PO4
Trace
GH booster(about 50% K2SO4, 3:1 Ca/Mg)

That hits all the items.

Some dose some extra Fe, I do not think it makes a difference really, I just add more Trace mix in general instead.

Most in the UK use less light than they do in the USA(the land of excess), so you will be avove any limiting values........except for CO2.

Watch and focus on CO2(consider getting some Easy Carb of the generic stuff from AE) and perhaps add a little Easy Carb for now till you get the CO2 gas dialed in right.

CO2 is the biggest issue in the hobby, nutrients are pretty easy, do not let it scare you or focus too much on them. Folks get very focused, too much so on nutrients.

CO2 is the biggie and the one that can kill fish and cause bad algae like nothing else can even come close too.

So spend your focus there.
Nutrients become very easy/old hat fast.


Regards,
Tom Barr

 

[Big_Bill]

Thanks for that Tom

At the minute I am only trying to prevent a minor outbreak of BBA from developing into anything worse. I've been very lucky in the last few years in that my tanks have been free of BBA.

About six weeks ago I moved the contents of a 30" x 12" x 18" tank into a 36" x 15" x 15".
The smaller tank had an old (3 years+) 18" T8 tube, possibly Gro LUX or similar, so it was a VERY LOW LIGHT setup, I only ever had very few plants in the tank, more to take the bare look off than anything, several clumps of Java fern & several of Anubias barteri 'Nana', along with 2 x Corydoras sterbae and 2 x Ancistrus sp. Water changes were very infrequent so NO3 was WELL over 100ppm & PO4 was never tested so I can only assume it was very high also. Though never any BBA!
Filtration was by an Eheim ext. 2215 filled with sintered glass media linked to another 2215 cannister (the pump in this doesn't work), filled with sponges ranging from coarse to fine and used as a pre-filter. I've never added CO2 or fed my plants in any way.

The new tank is heavily stocked with fish, 15 x Neon Tetras, 8 x Harlequins, 4 x Red Platys, 3 x Corydoras trilineatus + the original inhabitants, and has the same filter running on it.

The substrate is a 2"- 3" of a 50/50 mix of 3mm & 6mm gravel, I know, I need to drag myself out of the dark ages but I've gotten away with it up till now. Lighting is a 30", 25w T8 Arcadia "Original Tropical Lamp" so still low light, I will be adding a 30W T8 which is aimed more at plant growth soon, pH is 7.4 - 7.6 and KH is 1.9 - 2.2 so a CO2 of about 3 - 4 ppm I think, though probably lower. Don't know the GH. Temp is 75 deg.
At present it's just the Java fern, Anubias and a couple of Hydrocotyle verticillata I added last week.
For the first 4 or 5 weeks after transferring to the new tank 50%+ water changes were done once or twice weekly to reduce the NO3 & PO4 levels as low as possible, the water changes are made with RO/DI water re-mineralized with something akin to Kent RO right powder.
My thinking in the past has always been if the NO3 & PO4 are kept at extremely low levels there would be nothing for the BBA to feed on so it wouldn't be a problem. After searching this site I can now see how completely wrong I was.

The BBA appeared about four weeks after the transfer, so on the advice of my LFS I started dosing FlorinAxis at 3 drops/day, I have been dosing this for a week or so and have removed any leaves with BBA on them.
The Java fern looks ok and the Hydrocotyle doesn't look any different than when it was introduced. One piece of Anubias has flowered but some of the leaves on two other clumps are turning pale and others are falling apart at the edges or curling up, though there are some new healthy looking leaves appearing as well.

I was wondering if dosing with KNO3, KH2PO4, Trace and GH booster along with the Easy Carb or Excel would be enough in this setup.
I don't want to go high tech on this one I just want to try to keep the BBA away.

I have a 500+ litre setup with 4 x 54w T5s, which is marine at present but I will be converting it to F/W later this year and hope to set it up using CO2 and flourite & EI and fairly heavily planted at either end.

Cheers

Bill

 

[Big_Bill]

I'm a bit confused about the exact make-up of your GH Booster Tom.
In this thread you say it's,

"GH booster(about 50% K2SO4, 3:1 Ca/Mg)"

and in another it was

"By weight:

1 part CaSO4, 1 part MgSO4, 2 parts K2SO4.

Do not foret the hydrated fractions, 2 H2O and 7 H2O for the respective salts."

I think I saw a third version somewhere, might not have been on here, which included Fe & Mn.

Cheers

Bill

 

[Tom Barr]

GH booster by weight:

2 parts K2SO4
1 part CaSO4
1 part MgSO4

SeaChem Eq uses a little FeSO4 and MnSO4(not much at all)

But cost lots more.

BBA is a CO2 related issues in some form or the other, adding more, CO2 dosing not right etc.

At lower light, you have much less CO2 demand, nutrients really do noit matter unless they drive more CO2 demand.
since the tank is ideally light limited, then the nutrients can go very high and the CO2 demand is still low.

No BBA.

Likewise, in a higher light tank, folks add CO2 gas, so the CO2 is nice a non limiting as well, also, we add more nutrients and also: no BBA.

Higher light, poor CO2, nutrients can be either way, you still get BBA.

These are the basic overall observations.

Using Excel, or Esay carb is a solution, and will beat back and eventually kill off the BBA also. Cost effective? Maybe less so, CO2 is cheap over time though.

ADA AS is a good option as well in place of flourite.

Regards,
Tom Barr

 

[Gerryd]

Hi Tom,

ADA AS is a good option as well in place of flourite

Is this just general advice or related to the BBA issue noted above?

If BBA is (mostly/ALL?) c02 related, then how would/does ADA help?

Sorry if I am reading something into this that is not there.........

I understand that ADA is a better choice overall for planted tanks as then you have substrate nutes in case water column dosing is not existent or sub optimal/irregular or in case of both that the plants can take advantage of BOTH sources as they need.

Thanks as always,