Wet's EI modeling dosing calculator

Gerryd

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easttech;114553 said:
Ok, so starting to think about a fert regime and been looking at using EI with dry ferts, certainly cheaper I think that liquid lfs stuff and with a 300 gallon tank with about 350 gallons in total water column. I went to the calculator and was lost on the 1st question regarding each dose of stuff is XXX ppm? Not sure how I begin to analyze? Been reading and still not sure about the following: I currently do a 10% wc per day, just works out easier for me and a larger one with in tank cleaning once a week of about 30%. Can I use EI with my WC schedule or do I need to change my WC schedule? EI includes KN03, sorry my brain is going to explode, but is that the same as fish/food waste? If so how do I account for that in a moderately stocked tank?

thanks
John

Dude,

Try and relax... take a deep breath....

Dry powders will be much less expensive than most retail ferts, which can be very diluted..

You can use EI with almost any water change schedule, even a daily one...the larger 30% on day 7 will simply dilute any ferts in the tank. You can increase your dose on these days....remember that EI is designed with high light and good c02 in mind. but is designed to be FLEXIBLE as each tank is different.

Read the EI sticky for less technical folks. This has measurements in tsp/tblspns of each fert for a range of tank sizes. Pick a 50 gallon and multiply it by 7. That is how much you should dose. Then divide THAT by the number of days you want to dose. Dose AFTER your daily 10% w/c.

As an example, for my 220 gal, I dose the following daily:

1.5 tsp of kn03
1.5 tsp of kh2p04
1 tsp of csmb
.5 tsp of iron

A heavy fish load will simply add a bit more ferts to the water column, but this should prove no issue.

Here is a link where I and others have purchased dry ferts. I have used them for years..

http://www.aquariumfertilizer.com/index.asp?Option1=cats&Edit=2&EditU=1&Regit=2

Hope this helps.
 
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Tug

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That calculator was a working model. Wet's updated and easier to follow calculator can be found at, http://rota.la

With the improved calculator, once it gives you a dosing recommendation there is an option to see how much of the stuff (KNO3, etc.) is accumulating in your tank over time given your water change schedule. There is also an option for estimating the levels of stuff in the food you provide. EI doses provide ppm for each nutrient beyond which there is no benefit to the plants. That is to say, dosing less will not always cause deficiencies. As Tom mentions, factoring in things like light in terms of PAR, sediment based ferts, CO2, and total plant biomass can mean a smaller dose still provides sufficient nutrients. :joyous:

As a guide, if the concentration of stuff in your tank stays within the following ranges (these are not doses) you
are provide non-limiting nutrients.
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

In heavily planted tanks typical uptake rates per day under non-limiting conditions.(24 hours):
Admin;217 said:
EIUptake.jpg

  • NO3 1-4ppm
  • NH4 0.1-0.6ppm (do not dose NH4!It will cause algae)
  • PO4 0.2-0.6ppm
These rates do not assume that you will show deficiencies if you dose less than this, but adding more than these rates will not help further plant health.
This is a point that the aquarist needs to understand. Basically, it is extremely unlikely your plants will ever need more than these rates even at high light intensities. Adding enough nutrients to prevent anything from becoming deficient is the goal, not precise uptake and growth requirements.
 

easttech

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May 9, 2013
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Gerryd;114557 said:
Dude,

Try and relax... take a deep breath....

Dry powders will be much less expensive than most retail ferts, which can be very diluted..

You can use EI with almost any water change schedule, even a daily one...the larger 30% on day 7 will simply dilute any ferts in the tank. You can increase your dose on these days....remember that EI is designed with high light and good c02 in mind. but is designed to be FLEXIBLE as each tank is different.

Read the EI sticky for less technical folks. This has measurements in tsp/tblspns of each fert for a range of tank sizes. Pick a 50 gallon and multiply it by 7. That is how much you should dose. Then divide THAT by the number of days you want to dose. Dose AFTER your daily 10% w/c.

As an example, for my 220 gal, I dose the following daily:

1.5 tsp of kn03
1.5 tsp of kh2p04
1 tsp of csmb
.5 tsp of iron

A heavy fish load will simply add a bit more ferts to the water column, but this should prove no issue.

Here is a link where I and others have purchased dry ferts. I have used them for years..

http://www.aquariumfertilizer.com/index.asp?Option1=cats&Edit=2&EditU=1&Regit=2

Hope this helps.

Gerry,

This was taken from the Sticky for100 - 125 Gallon Aquarium
+/- 1 1/2 tsp KN03 3x a week
+/- ½ tsp KH2P04 3x a week
+/- 1.25 tsp once a week(water change only)
+/- ½ tsp (30ml) Trace 3x a week
50% weekly water change
less technical people on EI

For my tank with a water column of about 350 gallons my dosing would be roughly 3 x the above. Where I am getting confused is when in your post you say take the recommended dosing from this section an then divide it by 7 since I would be doing it daily and doing 10% daily water changes then a 30% one day a week. If the above reference was a total for a week then I would understand the divide by 7, since it is stating 3X a week how does that transalate into divide by seven? I actually perfer my 10% wc per day, get up in the morning have a coffee and change a couple of valves to change and i could just as easily do the fert dosing, but thinking I would prefer once a week is that possible? Once I get the hang of doing it manually and seeing how the plants respond I will go to auto dosing.

This is what I have purchased for dry ferts;
• Micros -
o Plantex CSM + B - 1 / 2 Pound
• Macros -
o Potassium Nitrate (KNO3) - 1 Pound
o Mono Potassium Phosphate (KH2PO4) - 1 / 2 Pound
o Potassium Sulfate (K2SO4) - 1 Pound

I assume I would not need to add Flourish since I have dry Micros? I will also be adding Seachem Iron

John
 

Gerryd

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Hi,

Sorry, my bad....

Take the dosing you have above and triple it like you said. Then triple it AGAIN to get your weekly dose. THEN divide by 7 to get a daily dose...

So for example, Kno3 is (1.5 tsp x 3) x 3 = 4.5 x 3 = 13.5 rounded up to 14. Then 14 / 7 = 2 tsp daily :) The rounding up is fine. The extra will not hurt anything.

Yes you can dose less often but the plants may experience a deficiency towards the end of the dosing cycle. I know there are uptake rates posted somewhere. Dry dosing is so easy, there is no reason not to do it at least bi-weekly.

The nominal EI schedule makes it easy is all. Every other day with a rest in between.....

EI is predicated on a MIN of 50% water changes weekly. This will prevent any possible toxic buildup. The amount and frequency is less important IME so long as 50% is reached. I do large 85% weekly but have 'cut back' to 60-70% only :) I have also done 2 or 3 50% of less during the week and never varied the dosing schedule. Is just easier to dose after a w/c as you are working with the tank anyway.

Note too that EI is adjustable and can be dosed higher or lower based on need. Note that more bio mass (growing plants) will require more c02 and other ferts. The reverse is also true...

Many of us have stopped using the Potassium Sulfate (K2SO4) as the Mono Potassium Phosphate (KH2PO4) supplies sufficient potassium. I would think the flourish will NOT be required. Extra iron will not hurt as far as I know. I know Tom has posted some high ppm value for iron in his tanks with no issue.

Hope this helps
 
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Tug

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Just to give another example for dosing a water column of about 350 gallons
and how the EI dosing chart is a range providing non limiting nutrients,
Gerry's formula using a 20-40 gallon tank.

So KNO3, (from the chart for 20 - 40 gallon tanks.)
  • 0.25 tsp x 8.75 = 2.2 tsp
  • 2.2 tsp x 3 days = 6.6 tsp (round up to 7)
  • 7 tsp / 7days = 1 tsp/day.
This shows Gerry's point about adjusting EI according to need but it also shows the large range of doses we can use to provide non-limiting nutrients.

Wet's calculator recommends a dose more in the middle
with a suggested daily dose closer to 1.5 tsp.


So it depends on the plant uptake and as you can see, there is a fairly large range for error without limiting nutrients.
 
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ShadowMac

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The calculator has an "EI daily" option, which I use.

Given the dosing is in a range, I don't think the 10% daily water changes should switch things up too much. If you observe some problems you can up the dosing slightly or maybe just calculate the daily dosing for the volume of your tank plus the volume of your water change ie add 70 more gallons since your weekly is 30% instead of 50% maybe just add 50 gallons and calculate for a tank of 400 gallons. Again a little more isn't harmful nor is a little less with EI dosing. Observation will tell you if you need more.

In my very high light tank I began dosing extra potassium because I noticed with KNO3 as the primary potassium source I was on the lower end of the range. I saw improvement.
 

Asmack Arabia

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hi,

i began using the rota.la calculator a few weeks ago. plotting my data, i got this result:


To reach your target of 3.2 ppm NO3 you will need to add 45.427 g KNO3 to your 500.0 mL dosing container. Add 5.0 mL of that mix to your 23.0 US gal aquarium to yield
Element ppm/degree
K 2.02
N 0.72
NO3 3.20

in short, it is:

Dose Yield Volume (gallons)
5ml 3.2ppm 23

aside from using the 5 ml dose daily, i want to use this solution and dose according to the result of my water tests. every pwc, i want to test the water and dose to make up for the difference in ppm levels, if any.

Reducing the Ratio to a Gallon of Water 3.2ppm / 23gallons = 0.139

Formula: 0.139vn = m

So to raise NO3 to 20ppm in a 23 gallon tank:

0.139 x 23 x 20 = 63.94ml

Is my calculation correct?
 

easttech

Member
May 9, 2013
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0
6
Gerryd;114795 said:
Hi,

Sorry, my bad....

Take the dosing you have above and triple it like you said. Then triple it AGAIN to get your weekly dose. THEN divide by 7 to get a daily dose...

So for example, Kno3 is (1.5 tsp x 3) x 3 = 4.5 x 3 = 13.5 rounded up to 14. Then 14 / 7 = 2 tsp daily :) The rounding up is fine. The extra will not hurt anything.

Yes you can dose less often but the plants may experience a deficiency towards the end of the dosing cycle. I know there are uptake rates posted somewhere. Dry dosing is so easy, there is no reason not to do it at least bi-weekly.

The nominal EI schedule makes it easy is all. Every other day with a rest in between.....

EI is predicated on a MIN of 50% water changes weekly. This will prevent any possible toxic buildup. The amount and frequency is less important IME so long as 50% is reached. I do large 85% weekly but have 'cut back' to 60-70% only :) I have also done 2 or 3 50% of less during the week and never varied the dosing schedule. Is just easier to dose after a w/c as you are working with the tank anyway.

Note too that EI is adjustable and can be dosed higher or lower based on need. Note that more bio mass (growing plants) will require more c02 and other ferts. The reverse is also true...

Many of us have stopped using the Potassium Sulfate (K2SO4) as the Mono Potassium Phosphate (KH2PO4) supplies sufficient potassium. I would think the flourish will NOT be required. Extra iron will not hurt as far as I know. I know Tom has posted some high ppm value for iron in his tanks with no issue.

Hope this helps

Here is what I am currently dosing;

Micros
½ tsp X 3 = 1.5 tsp x 3 = 4.5 tsp rounded up to 5, 5/7= ¾ tsp micros daily
Kno3 is (1.5 tsp x 3) x 3 = 4.5 x 3 = 13.5 rounded up to 14. Then 14 / 7 = 2 tsp Kno3 daily
KH2P04 ½ tsp X 3 =1 ½ tsp X 3 = 4 ½ tsp rounded up to 5. 5 / 7 = ¾ tsp KH2P04 daily, maybe not needed
K2S04 1.25 tsp week after water change, 1.25 X 3 = 4 tsp weekly
Iron


Hope my math is correct. I am currently a little concerned as my Nitrates have climbed to 50 ppm. I am 3 days away from y 30% water change. I just added some semi adult discus so my higher nitrates are putting me on edge. I am thinking my light/plant load and fish bio contribution plus what I am adding per above is not being consumed as expected or I am adding too much with fish load and dosing that is creating this. Under normal circumstances I think this would be fine, with Discus and their sensitivity to water quality that I could be heading for trouble? Suggestions, maybe cutting the KNo3 down? Uping the lights. Thoughts?

Thanks.
 

Tug

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Not every number can be rounded up - some are rounded off.

John,
Gerry watches over us like a hawk. I couldn't steer you wrong, even if I wanted. I should also remind e1 that the thread is about Wet's calculator. I've played along because it relates to the EI chart and has been sort of interesting.

Your micro dose for CSM+B trace,
½ tsp X 3 = 1.5 tsp x 3 = 4.5 tsp rounded up to 5, 5/7= ¾ tsp micros daily
Math and measuring errors aside, I would consider the 3/4tsp dose about right for daily dosing your tank. :surprise:
If you ask wet's calculator it suggests, 1 tsp/daily.

If you are trying to dose an equivalent amount of CSM+B to what Gerry doses,
you would add anywhere between 1.5 and 1.75 tsp a day.


KNO3,
you noticed the accumulation of NO3 in your tank is about 50ppm and other then perturbation, no real harm has come of it. Still, you might try the calculator's recommended 1.5tsp/daily dose and see if the NO3 levels off at a slightly lower level. It is very possible that a 1tsp/daily dose is more then sufficient for your tank.

1.5tsp/daily KNO3 adds 3.6ppm of NO3 to a 350 gallon water column.
You would be growing a heavy plant load with really good light and CO2 to need more then that level of nitrate in a day.​

KH2PO4;
KH2P04 ½ tsp X 3 =1 ½ tsp X 3 = 4 ½ tsp rounded up to 5. 5 / 7 = ¾ tsp KH2P04 daily, maybe not needed
And, you are right.
That dose provides three times the PO4 your plants will be needing.

I am using the 1/16tsp, from the charts 20-40 gallon tank range to find the dose for 350 gallons,
your PO4 levels will be non-limiting and inline with EI.
If you check wet's calc., it is very close. http://rota.la

0.0625 (350/40) = .5 tsp rounded off.
0.5tsp x 3days = weekly dose for your 350 gallons of water, 1.5 tsp/week
divide by 7 = 0.21 tsp (about 1/5 tsp or ruffly 1/3 your current dose).
Dosing 1/4 tsp/daily provides about 0.7ppm of PO4 to your tank.
More PO4, then your plants will need to grow healthy.​

K2SO4;
K2S04 1.25 tsp week after water change, 1.25 X 3 = 4 tsp weekly
:confused: Why not 3tsp, why add any? Until you know you need the additional K+, 3 tsp/week is all I would add.

John's OP;
easttech;114553 said:
Ok, so starting to think about a fert regime and been looking at using EI with dry ferts, certainly cheaper I think that liquid lfs stuff and with a 300 gallon tank with about 350 gallons in total water column. I went to the calculator and was lost on the 1st question regarding each dose of stuff is XXX ppm? Not sure how I begin to analyze? Been reading and still not sure about the following: I currently do a 10% wc per day, just works out easier for me and a larger one with in tank cleaning once a week of about 30%. Can I use EI with my WC schedule or do I need to change my WC schedule? EI includes KN03, sorry my brain is going to explode, but is that the same as fish/food waste? If so how do I account for that in a moderately stocked tank?

thanks
John
Really, try it again. http://rota.la
 
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Tug

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The problem with using the calculator for this problem, while there is an option for daily water changes of 10%, it does not account for the additional weekly 30% WC. I'm not sure if I would bother to calculate for the additional weekly 30% water change. :cool:

ShadowMac;114801 said:
The calculator has an "EI daily" option, which I use.

Given the dosing is in a range, I don't think the 10% daily water changes should switch things up too much. If you observe some problems you can up the dosing slightly or maybe just calculate the daily dosing for the volume of your tank plus the volume of your water change ie add 70 more gallons since your weekly is 30% instead of 50% maybe just add 50 gallons and calculate for a tank of 400 gallons. Again a little more isn't harmful nor is a little less with EI dosing. Observation will tell you if you need more.

In my very high light tank I began dosing extra potassium because I noticed with KNO3 as the primary potassium source I was on the lower end of the range. I saw improvement.

As long as your daily dose provides the typical uptake rates for nutrients the additional 30% water change at the end of the week should not be of any consequence. As Gerry points out,
You can use EI with almost any water change schedule, even a daily one...the larger 30% on day 7 will simply dilute any ferts in the tank.

A heavily planted tanks typical uptake rates per day under non-limiting conditions.(24 hours):
Admin;217 said:
EIUptake.jpg

  • NO3 1-4ppm
  • NH4 0.1-0.6ppm (do not dose NH4!It will cause algae)
  • PO4 0.2-0.6ppm
These rates do not assume that you will show deficiencies if you dose less than this, but adding more than these rates will not help further plant health.
This is a point that the aquarist needs to understand. Basically, it is extremely unlikely your plants will ever need more than these rates even at high light intensities. Adding enough nutrients to prevent anything from becoming deficient is the goal, not precise uptake and growth requirements.
 
Last edited by a moderator:

easttech

Member
May 9, 2013
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Tug;114982 said:
John,
Gerry watches over us like a hawk. I couldn't steer you wrong, even if I wanted. I should also remind e1 that the thread is about Wet's calculator. I've played along because it relates to the EI chart and has been sort of interesting.

Your micro dose for CSM+B trace,

Math and measuring errors aside, I would consider the 3/4tsp dose about right for daily dosing your tank. :surprise:
If you ask wet's calculator it suggests, 1 tsp/daily.

If you are trying to dose an equivalent amount of CSM+B to what Gerry doses,
you would add anywhere between 1.5 and 1.75 tsp a day.


KNO3,
you noticed the accumulation of NO3 in your tank is about 50ppm and other then perturbation, no real harm has come of it. Still, you might try the calculator's recommended 1.5tsp/daily dose and see if the NO3 levels off at a slightly lower level. It is very possible that a 1tsp/daily dose is more then sufficient for your tank.

1.5tsp/daily KNO3 adds 3.6ppm to a 350 gallon water column.
You would be growing a heavy plant load with really good light and CO2 to need more then that level of nitrate in a day.​

KH2PO4;

And, you are right.
That dose provides three times the PO4 your plants will be needing.

I am using the 1/16tsp, from the charts 20-40 gallon tank range to find the dose for 350 gallons,
your PO4 levels will be non-limiting and inline with EI.
If you check wet's calc., it is very close. http://rota.la

0.0625 (350/40) = .5 tsp rounded off.
0.5tsp x 3days = weekly dose for your 350 gallons of water, 1.5 tsp/week
divide by 7 = 0.21 tsp (about 1/5 tsp or ruffly 1/3 your current dose).
Dosing 1/4 tsp/daily provides about 0.7ppm of PO4 to your tank.
More PO4, then your plants will need to grow healthy.​

K2SO4;

:confused: Why not 3tsp, why add any? Until you know you need the additional K+, 3 tsp/week is all I would add.

John's OP;

Really, try it again. http://rota.la

Thanks Tug!

So far growth is not knocking me off my feet, seems kind of stagnant. I get the impression any changes made should be measured. In other words, if I increase light intensity a little, then let it be for awhile and see the difference, same with any changes in Co2 or ferts, otherwise you can very easily get confused as to what change caused the improvement or degradation. Just kind of wondering how long should you wait before seeing a change, a week, a day?

Was also curious on Iron. I am currently dosing per Seachems suggestion, was curious on suggestion for a dry form of Iron and also I noticed there are a few different types. Any suggestions here would be appreciated.

Thanks
 

mrp

Junior Poster
Oct 6, 2013
1
0
1
just next EI calculator

Hi everyone,
I've made little EI simulator

Now, I am working on upgrade of calculating logic, like concentrations tresholds, reverse calculation of sulutions, toxicity, etc etc. I would like to know your opinion
 

TyS

Subscriber
Feb 12, 2014
10
0
1
Hi,
A very simple (and probably stupid ) question here ..
When using Wet's calc to determine amounts in ppm for a tank, are the results what is calculated for a weeks dosing in total? Or is this the daily amount required ?

Thanks and sorry for the newbieness!! :)
 

BNanoNewbie

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I have tried using the search feature in an efforts to find a fertilization guide. Something that will allow me to look at each method before setting up. As a newbie, I like to make sure I do my research before jumping right in. Tend to move around once I've started on a project, but like to build a solid background of knowledge first. Can anyone point me in the right direction?
 

rajkm

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I have tried using the search feature in an efforts to find a fertilization guide. Something that will allow me to look at each method before setting up. As a newbie, I like to make sure I do my research before jumping right in. Tend to move around once I've started on a project, but like to build a solid background of knowledge first. Can anyone point me in the right direction?

EI, PPS, PPS Pro, PMDD. These are the top 4 methods. You can google them and know the pros and cons.
Fertilization is secondary.. concentrate on good practices like water changes, trimming, CO2 Stability, controlled light levels.
 
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