Help me make EI solutions for my tanks. - The Planted Tank Forum
Old 05-03-2017, 03:02 PM Thread Starter
Algae Grower

Join Date: Apr 2017
Posts: 7
Help me make EI solutions for my tanks.

Hi everyone. After several months of dosing PPS Pro in my high tech tanks I have decided to switch over to the EI method of dosing. I use Green Leaf Aquariums PPS Pro pack which includes dry ferts and two 500ml bottles. I need some help converting these materials into EI concentrations. I have a 29 gallon tank, a 12 gallon tank, and a 20 gallon tank. I'd like to use the two 500ml bottles and dose all three tanks using syringes form these solutions. I'm a little confused as to what doses I should plug into Rotala butterfly and how to make the solutions work for all three tanks.
McGodes is offline

Old 05-03-2017, 04:39 PM
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Join Date: Dec 2004
Location: Rome
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Hello McGodes, I will make the calculation for 10G. You can then simply multiply the amount to dose by 2.9 for the 29G, 1.2 for the 12g and 2 for the 10g.

As I understand it you would like to dose similar to EI levels with the bottles that you have created for PPS-Pro according to the instructions offered by GLA ( Our PPS-Pro Fertilizer Pack ? Just Mix & Dose ? Planted Tank Blog )

K2SO4 – 29.3 grams
KNO3 – 32.6 grams
KH2PO4 – 2.9 grams
MgSO4 – 20.2 grams ( Assume GLA is inattentive with the information it provides and actually means the heptahydrate here)
in bottle so the total volume is 500ml
Plantex CSM+B – 28.6 grams
in bottle so the total volume is 500ml

This means you will have a conc. in the bottles of
K2SO4 – 58.6mg/mL
KNO3 – 65.2mg/mL
KH2PO4 – 5.8 mg/mL
MgSO4 *7H2O– 40.4 mg/mL

Based on mass percent of the above substance we can extract
K2SO4 – 58.6mg/mL - 26.3 mg/mL K
KNO3 – 65.2mg/mL - 25.21 mg/mL K ... 39.99mg/mL NO3
KH2PO4 – 5.8 mg/mL - 1.66 mg/mL K ... 4.047mg/mL PO4
MgSO4*7H2O – 40.4 mg/mL - 3.98 mg/mL Mg

This means
K ... 53.17 mg/mL
NO3 ... 39.99 mg/mL
PO4 ... 4.047 mg/mL
Mg ... 3.98 mg/mL

For a 10G tank adding 30mL of solution will give you (*30/37,9)
K ... ~ 42,1 mg/L
NO3 ... ~31,7 mg/L
PO4 ...~3.2 mg/L
Mg ... ~3.2 mg/L

So it looks like the total volume per week should be 30mL, 3 doses of 10mL every other day for example.

For Plantex,you can do the same thing for every element...But 5ml per week adds about 0.5mg/mL Fe

Now you know how to calculate your dose without relying on rotala.

On hiatus till later this year
dukydaf is offline
Old 05-03-2017, 05:41 PM Thread Starter
Algae Grower

Join Date: Apr 2017
Posts: 7
Thank you for working that out for me. I follow how you derived conc. in bottles. I'm not sure how you derived mass percent. Is that chemistry work? Essentially calculating the mass of K in the total K2SO4 dissolved in the bottle? I follow how you came up with the values of K, NO3 etc in mg/mL using the mass percent extraction. I don't follow how you made the conclusion highlighted in bold. On a side note, in my research I've discovered that dosing the high light recommendation for GLA PPS Pro yields similiar PPMs of NPK and micros that EI reccomends:

Tom Barr's Reccomended Ranges:
CO2 range 25-35ppm
NO3 range 5-30ppm
K+ range 10-30ppm
PO4 range 1.0-3.0 ppm
Fe 0.2-0.5ppm or higher (?)
GH range 3 degrees ~ 50ppm or higher (The Estimative Index of Dosing, or No Need for Test Kits - Aquarium Plants - Barr Report)

According to GLA if I dose 2mls of macros/10gal and .2mls of micros/10 gal my results will be comparable to EI and as follows:

High light (PPS Pro)
PPS-Pro Solution #1, 2ml per 10 gallon or 40 L
PPS-Pro Solution #2, 4 drops per 10 gallon or 40 L
Water change 50% once a week
This limits water column nutrient levels to 28 ppm NO3, 2.8 ppm PO4, 36 ppm K, 2.8 ppm Mg, 0.28 ppm Fe(TE).
(1 ml = 20 drops) (Our PPS-Pro Fertilizer Pack ? Just Mix & Dose ? Planted Tank Blog)

I'm wondering if using this high light PPS Pro method is the easier way to go given my current habit of daily macro/micro dosing.
McGodes is offline

Old 05-03-2017, 06:38 PM
Planted Tank Enthusiast

Join Date: Jul 2014
Location: USA
Posts: 566
Got you covered here. Get his diy EI package. Comes with two bottles one for micros and one for macros. Add a water and dry pack of each into the bottles, shake well, and your good to go. Get his GH booster as well and add with your weekly water change. Then go to a drugstore and they have 5ml syringes for free. Since your not doing super high tech, you will probably be fine with say ½ EI dosing (not an expert though). So 3.75ml a day. Should last you a long time and only about 35 bucks shipped. The instructions are for a 20 gallon tank so it would be easy to do the math for a 30.
sevendust111 is offline
Old 05-03-2017, 07:29 PM
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Join Date: Dec 2004
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Quote:
Originally Posted by McGodes View Post
Thank you for working that out for me. I follow how you derived conc. in bottles. I'm not sure how you derived mass percent. Is that chemistry work? Essentially calculating the mass of K in the total K2SO4 dissolved in the bottle? I follow how you came up with the values of K, NO3 etc in mg/mL using the mass percent extraction. I don't follow how you made the conclusion highlighted in bold. On a side note, in my research I've discovered that dosing the high light recommendation for GLA PPS Pro yields similiar PPMs of NPK and micros that EI reccomends:

According to GLA if I dose 2mls of macros/10gal and .2mls of micros/10 gal my results will be comparable to EI and as follows:
This limits water column nutrient levels to 28 ppm NO3, 2.8 ppm PO4, 36 ppm K, 2.8 ppm Mg, 0.28 ppm Fe(TE).
Allow me to start from the end... be careful on the wording existing on GLA site ... "limits" is the important word. That does not mean it actually adds that much. What does it mean, under what conditions is this limited ? You have to ask GLA... If you look at the math a 2ml dose in 10g would add ~2ppm NO3, 0.2ppm PO4 etc Doesn't look like EI to me.

Glad I could help with the calculations.
The mass percent is based on the atomic weight of the molecule/ion/element, so yes a chemistry thing. Take water for example :
H20 -
Total atomic weight 2*H+1*O = 2*1+1*16=2+16=18
The mass percent of O in the water molecule is then 88,9% (16/18*100). This then can also be applied at a larger scale meaning that from 100kg water, O would be responsible for 88.9kg. I am only looking at the K from the K2SO4 and treating it as if I could weigh it alone. In reality it is not possible to weight a ion from the molecule but we can still calculate its weight at a theoretical basis. As the K+ would fully dissolve (hopefully) , from K2SO4, we can then calculate its concentration.

Next. How I got from a bottle having a conc. of NO3 ... 39.99 mg/mL to 30mL of solution in 10G giving NO3 ... ~31,7 mg/L

NO3 ... 39.99 mg/mL means that :
1ml of solution has 39.99mg
30ml of solution have 30*39.99=1199.7mg

If we add this amount in 1L we would get a conc of 1199.7mg/L.
The same amount in 37,9L (10G) would result in 1199.7/37.9=31.65mg/L

Well actually I just used a formula but this gets you trough the thought process.

On hiatus till later this year
dukydaf is offline
Old 05-03-2017, 07:32 PM
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Join Date: Jan 2014
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Quote:
Originally Posted by sevendust111 View Post
Got you covered here. Get his diy EI package. Comes with two bottles one for micros and one for macros. Add a water and dry pack of each into the bottles, shake well, and your good to go. Get his GH booster as well and add with your weekly water change. Then go to a drugstore and they have 5ml syringes for free. Since your not doing super high tech, you will probably be fine with say ½ EI dosing (not an expert though). So 3.75ml a day. Should last you a long time and only about 35 bucks shipped. The instructions are for a 20 gallon tank so it would be easy to do the math for a 30.

Not sure who you're trying to reference or what you've got covered but the OP already has Ferts and bottles. He was looking for mixing instructions.
Kubla is offline
Old 05-03-2017, 10:31 PM Thread Starter
Algae Grower

Join Date: Apr 2017
Posts: 7
Thank you. I do have an educational background that included some chemistry so this isn't completely foreign to me. However it has been a while. I really appreciate you working out the thought process for me. To draw from a famous proverb, I'd rather be taught how to fish than just be given a fish. I'm going to give this a try and see what type of results I get. The ppm of K seems a little high compared to Tom's recommendation in the article I sited. Also, I'm used to administering small doses in my tanks with PPS Pro so the solutions last months. With EI and the current concentrations of these solutions, I'll go through these bottles much quicker. After I deplete the solutions it seems more logical to switch over to dosing dry ferts directly into the tank given. I saw that Tom reccomends some general guidelines for dosing dry ferts:

General Dosing Guideline for High Light and well planted aquariums.

10- 20 Gallon Aquariums
+/- 1/8 tsp KNO3 (N) 3x a week
+/- 1/32 tsp KH2PO4 (P) 3x a week
+/- 1/4 tsp GH booster once a week(water change only)
+/- 1/32 tsp (2ml) Trace Elements 3x a week
50% weekly water change

20-40 Gallon Aquariums
+/- ¼ tsp KN03 3x a week
+/- 1/16 tsp KH2P04 3x a week
+/- 1/2 tsp GH booster once a week(water change only)
+/- 1/16 tsp (5ml) Trace Elements 3x a week
50% weekly water change
(EI light: for those less techy folks - Aquarium Plants - Barr Report)

Would this be a good guideline to follow if and when I make the switch? Do most people using EI make solutions or dose right into the tank?

McGodes is offline
Old 05-06-2017, 01:02 AM
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Join Date: Dec 2004
Location: Rome
Posts: 1,273
Hope it was easy to follow. Sometimes I restate simple things because experts like the confirmation that they know all the beginners stuff, students benefit from repetition and smart people enjoy learning something new.

My advice for next time would be to drop the K2SO4( KNO3 adds enough K) and mix 30x the weight of KNO3, KH2PO4 stated in my first post. Than the bottle will last 30 times more. Check the solubility of the 2 first.

You can make the switch at any time really. People do both, from my point of view for small aquariums it is impossible to obtain a degree of accuracy when dosing solids and I do not like my fish to nibble on the granules. It helps that dosing pumps work with liquids

Yeah, so pet-peeve of mine... while I understand why Tom Barr and Co. did this, I do not agree with them endorsing it. The rationale is simple, since we are working under the philosophy of "add more than enough"... you do not have to be exact; since it is for everybody, this is a way for everybody to do it. Does it mean you should do it ? Your choice, below my counter argument ( may sound sometimes smug to some people)

Since we want to obtain a target concentration of mg/L in the aquarium, it makes sense that we would measure the weight of desired fertilizer.
TEASPOONS ARE NOT MEASURES OF WEIGHT. There, I said it. They are at best used to measure volume of liquids. Try this, take 5 teaspoons of a salt and weight them on a precise scale, calculate mg/teaspoon. Take 10, take 50, take 5 again, ask your friend to do the same... chances are that every time you get different amounts.

Add to this that we are dealing with salts, which have various sized crystals depending on the manufacturer standards, industry grade will be coarse, lab grade will be fine. How do you think this affects the density of the salts... and thus the weight of salt in your Volume measuring tool, the teaspoon. According to my own observations and that reported by other members online you can easily introduce a 2xtarget amount error and between users it can vary by as much as 5x. And then you see people on the forum saying that they use EI and have N deficiency or have 80+ppm NO3...might this be one factor ?

For most people on this site I do not find it too much of a trouble to use a scale. If you need to dose too little to accurately weight make a solution. Just my rationale.

On hiatus till later this year
dukydaf is offline

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