PPS PRO vs EI

James Burcham

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When purchasing my fertilizer I mistakenly bought a PPS PRO fert package instead of an EI one. What are your thoughts/experience with the two methods?
 

dw1305

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Hi all,
When purchasing my fertilizer I mistakenly bought a PPS PRO fert package instead of an EI one. What are your thoughts/experience with the two methods?
I always think about fertilisers in terms of "ions", plants can only take up fertilisers as ions and every NO3- ion etc. is the same as every other NO3- ion, it doesn't matter where they come from.

If the PPS Pro package come as individual dry salts?, (rather than ready mixed), you can just as easily make up the EI recipe, rather than the PPS Pro one.

The PPS Pro recipe is here <"PPS Pro">. You could work out how many ppm (Mg/L) of each ion you supply via the <"Rotala Butterfly nutrient calculator">.

Last thing the PPS Pro web site lists magnesium sulphate as the anhydrous MgSO4, but it will actually be the heptahydrate (Mg SO4.7H2O) and only 10% Mg.

cheers Darrel
 

dw1305

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Hi all,
The kit I bought is here.
https://greenleafaquariums.com/products/pps-pro-aquarium-fertilizer-package-bags.html

So if I'm understanding correctly. The PPS PRO is just a lower dosage the the EI?
By the look of it.

All successful fertilisers are going to be similar, plants need all fourteen of the essential elements for growth, <"just in vastly different amounts">.

There are a limited number of chemical compounds that are fish safe (you can't use <"urea"> (CO(NH2)2) or ammonium (NH4+) as your <"nitrogen source">), cheap and fully soluble. The advantage of KNO3 and KH2PO4 is that both cation (K+) and anion (NO3- and PO4---) etc. are nutrients.

The mono-potassium phosphate formula should be "KH2PO4", if you want to put it into the Rotala Butterfly calculator.

cheers Darrel
 

James Burcham

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So I'm still feeling a little dumb in regards to ferts. In the dosing instructions for the PPS PRO method it states to dose both macro and micro (separate solutions) at the same time but I've read in other posts and on the EI method to dose them on different days.??:banhappy:??

Also I have not picked up a TDS meter yet. In the meantime is there any other way to know I'm dosing enough?

I'm attaching a pic of my current dosage. I'm using the highest volume one, the high light dose. However I haven't dropped down to 1 WC a week yet. I'm currently performing a WC every 2 days.

Screenshot_20190710-080444_Chrome.jpg


https://sites.google.com/site/aquaticplantfertilizer/home/chemicals
 

dw1305

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Hi all,
PS PRO method it states to dose both macro and micro (separate solutions) at the same time but I've read in other posts and on the EI method to dose them on different days.
You can potentially get precipitation of phosphate (from the macro) and iron (from the micro mix) compounds. Because you have a relatively dilute feed with PPS, it is less of an issue.
Also I have not picked up a TDS meter yet. In the meantime is there any other way to know I'm dosing enough?
Just look at <"the plants">, if they are a nice green and growing you are dosing enough. A <"floating plant"> is the best "canary", because it takes CO2, and PAR, out of the equation.
I'm attaching a pic of my current dosage. I'm using the highest volume one, the high light dose. However I haven't dropped down to 1 WC a week yet. I'm currently performing a WC every 2 days.
If the plants are looking OK? Just keep on going.

Once you have the TDS meter, measure the TDS every day for a week or so. That will give a datum range. At that point I'd go to one water change a week, and then see how much the TDS rises over the next couple of weeks.

If it remains near the datum range one water change is fine, if it continues creeping up you can either go back to two water changes or lower the dosing to the "medium light" option.

cheers Darrel
 

James Burcham

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Once you have the TDS meter, measure the TDS every day for a week or so. That will give a datum range. At that point I'd go to one water change a week, and then see how much the TDS rises over the next couple of weeks.

Thanks Darrel. What levels am I needing to achieve?

If it remains near the datum range one water change is fine, if it continues creeping up you can either go back to two water changes or lower the dosing to the "medium light" option.

How much of an increase over the week would you consider too great?
 

dw1305

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Hi all,
What levels am I needing to achieve?
There isn't really a value, it is going to depend upon the starting point. Have a look at Jordi's (@parotet's) comments in <"Setting up....">.
How much of an increase over the week would you consider too great?
It would really just be if the value continually rose, eventually it will stabilise whatever happens.

I keep soft water fish in rain-water so I aim to keep under 200 microS and over about 60 microS. When the water gets below about 100 microS the plants definitely start to suffer, presumably at that point you have very few ions of any description. I just want some growth, I'm not looking optimal growth.

Our tap water is good quality, but hard, and somewhere around 650 microS, nearly all as Ca++ and HCO3- ions. I'd probably aim for around 800 microS if I used tap water as a starting point.

cheers Darrel
 

James Burcham

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Here are my TDS readings from the first week of using the meter.

Tap - 360
After 50% WC
Mon - 370
Tue - 383
Wed - 398
Thur - 409
Fri - 420
Sat - 427
50 % WC
Sun - 417

@dw1305 I would have figured it would have gone down a bit more after the WC. This was the first week of going without a WC. What do you think of these numbers?
 

Jayefc1

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You could always change more water 50% is simply a guide line I like to do 70% weekly that brings my TDH back down to just above my tap level and I find it completely resets the tank then I start again
Cheers
Jay
 

James Burcham

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I did move some plants around prior to the WC. I'm thinking the TDS count was a bit higher after that. I didn't test it before the WC. I completely spaced taking this into account. :facepalm:
 

Zeus.

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Here are my TDS readings from the first week of using the meter.

Tap - 360
After 50% WC
Mon - 370
Tue - 383
Wed - 398
Thur - 409
Fri - 420
Sat - 427
50 % WC
Sun - 417



Total dissolved solids
Quote
Electrical conductivity of water is directly related to the concentration of dissolved ionized solids in the water. Ions from the dissolved solids in water create the ability for that water to conduct an electric current, which can be measured using a conventional conductivity meter or TDS meter. When correlated with laboratory TDS measurements, conductivity provides an approximate value for the TDS concentration, usually to within ten-percent accuracy.
The relationship of TDS and specific conductance of groundwater can be approximated by the following equation:

TDS = keEC
where TDS is expressed in mg/L and EC is the electrical conductivity in microsiemens per centimeter at 25 °C. The correlation factor ke varies between 0.55 and 0.8.

Unquote

so could be you TDS meter/pen and was the water at the same temp each time

I think the results are with acceptable limits
 

dw1305

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Hi all,
@dw1305 I would have figured it would have gone down a bit more after the WC
Yes, probably should have done.
I’d’ve expected it to drop to ~ 390 - 400 after 50% water change
That is what I'd expect as well, conductivity is a linear value (at the values that interest us) so the ppm TDS reading should be somewhere near (360 + 417)/2.
where TDS is expressed in mg/L and EC is the electrical conductivity in microsiemens per centimeter at 25 °C. The correlation factor ke varies between 0.55 and 0.8.
The 0.55 ke value is where the major salt in the water is sodium based (so usually NaCl). All the meters I've seen in the UK use ke 0.64 as a default, which is the conversion factor when Ca++ and HCO3- (from CaCO3) are the most frequent ions present.

Temperature is a bit of a strange one. There are two factors, most salts are more soluble at higher temperatures, but carbonates are less soluble (their solubility depends upon the CO2 concentration in the water, and gases are less soluble at higher temperatures). The other effect is to do with viscosity, a decrease in the viscosity of water increases the mobility of ions in water. Warm water is "thinner", so an increase in temperature increases conductivity. Because of differing ionic composition it isn't an exact conversion, but conductivity increases at somewhere near 2-3% per 1°C increase in temperature.
.......some plants around prior to the WC, I'm thinking the TDS count was a bit higher after that.
Sounds likely.
could always change more water 50% is simply a guide line I like to do 70% weekly that brings my TDH back down to just above my tap level
I'd probably give it another week, and then if the TDS values are still rising up the water change frequency (or volume).

cheers Darrel
 

James Burcham

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Fargo, nd USA
so could be you TDS meter/pen and was the water at the same temp each time

Well the temp stays at a pretty consistent 72 deg farenheit except during this time of year the cold water in my building seems to be a little warmer. So after WC the temp in the tank rises to about 76 deg farenheit until it cools back down to room temp. That being said I'll wait for the temp to drop back down after WC to check TDS.
 
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