Why the big difference?

are you confusing one calculator for another?

seamchems calculator is setup for seachem product bottle concentration.
to dose according to any given volume of water


EI dosage calculators are set up for the given concentration
you'ed mix the dry ferts into a 500 ml bottle. and dose accordingly to any given volume of water.to achieve a given ppm.


I dose all seachem and use their recommendation chart.



another thing seachem assumes a 5% weekly water change.

EI dosing assumes a 50% weekly "reset" water change, and an over abundance of nutrients.

seachem may be set up to mimic a weekly macro & micro offset daily
dosing. but not the EI concentrations

buckwheet said:

are you confusing one calculator for another?

seamchems calculator is setup for seachem product bottle concentration.
to dose according to any given volume of water


EI dosage calculators are set up for the given concentration
you'ed mix the dry ferts into a 500 ml bottle. and dose accordingly to any given volume of water.to achieve a given ppm.


I dose all seachem and use their recommendation chart.

another thing seachem assumes a 5% weekly water change.

EI dosing assumes a 50% weekly "reset" water change, and an over abundance of nutrients.

seachem may be set up to mimic a weekly macro & micro offset daily
dosing. but not the EI concentrations

Click to expand...

I am talking about this calculator http://calc.petalphile.com/
I chose "premixed fertiliser" and then ,the Seachem P and K ,to calculate for the EI/low light weekly.Since we cannot measure the K in our tanks ,I tried to measure the PO4 ,right after dosing(1 ppm according to the calc) ,and then ,measure in the end of the week ,right before the water change.I know that tests aren't accurate ,I just wanted to make an idea about the uptake.
In the end of the week the tests still showed PO4 being present ,but the color was really light (0.2-0.4 ppm) - to say it in numbers.

Which means I can safely lower my dosing ,until the test shows almost no PO4 before the water change ,right?and ,of course ,keep an eye on the plants ,and read their signals - better than any test ,from what I hear ,and makes sense.
That way I will find that so called "critical point" that people talk about when using the low light/no Co2 method.From there ,I can safely begin to postpone WC ,until maybe ,once a month ,or once every 2 months.
I may be wrong about this ,that's why I need help ,to make sure what I intend to do is right.Feel free to chime in.

well, I'm talking about the original question(s) "Why the big difference?"

maybe what I should have said is, are you confusing one method and/or product for another?



I've been dosing according to the Yet Another Nutrient Calculator ,for a while now.- EI Low Light/Weekly method
I dose Flourish K and P.I just noticed that ,on the Flourish P bottle ,they recommend 2.5 ml for 80 liters ,once or twice a week.

yup, that's what they recommend! for their product!
they are NOT trying to achieve a 1 ppm of PO4 "EI Low Light/Weekly method"
or any other EI method. you are!



To reach your target of 1 ppm PO4 you will need to add 19 mL Flourish Phosphorus to your 80.0 L aquarium to yield the desired 1 ppm of P .WTF??


right.........?
according to Wet's EI modeling calculator to achieve a 1 ppm of seachem PO4 for a "EI Low Light/Weekly method"
add 19ml of seachem phosphorus!

(seachems calculator comes out to 20g/ current 0ppm/ desired 1.00ppm/
required 3.3 caps or 16.6 ML) but I guess that would be splitting hairs!

to save yourself a bunch of confusion of mixing methods and or product. why don't you go ahead and get some dry KH2PO4. mix 11.463g into a 500ml container. Add 5.0 mL of that mix to your 80.0 L aquarium to get 1.00ppm of PO4.
do what ever water changes a "EI Low Light/Weekly method" recommends
stick to one method!
and one "product (dry/or seachem) just to keep it simple!


back to the original question, "Why the big difference?"
seachem does not mix 11.463g of KH2PO4 into their 500ml bottles!!!:icon_wink