Oh I just like to manage K dosing seperately.
I want to set my GH and KH parameters as constant as possible at water change time. I mix KNO3, KH2PO4, and K2SO4 in a stock soulation for all my macro needs.
Hmm... Looks like I have some more studying to do. I want to make sure I understand how the H20s affect those Calcium and Magnesium compounds as I calculate concentrations.
Leaning towards CaSO4 for the Calcium part so far.
Thanks for your reply.
I think it is quite unrealitistic to seek constant
ppms, rather, a better more flexible method is to have a range
of ppms that you target then you need not be so critical with dosing, measuring or in the routine etc. Even the best test kits and measuring methods which can be laborious when done properly have error ranges than make that goal unrealitistic.
There's a way around it but involves a huge reservior and a small tank.
But having a relative range of nutrients is the key thing here, KH is not particularly important other than measuring CO2, there are ways to get around that parameter(KH) as well.
You can read the EI article I have on my site and see if that will make life easier. After time, few aquarist test and rather would watch their plants, garden,scape etc rather than play around with the ferts.
While important, the lion's share of folks' issues and algae related problems are with CO2, you would be much wiser to focus such energy there than with ferts.
As long as there is ample supplies over a wide range, especially for GH more than any other and K+, you have much bigger issues to fret over.
I've gone from 2 to 24 degrees with GH. Many keep about 4-10 ranges.
K+ is more difficult to measure, I use a colorimeter which is very $$, not something a hobbyists might use, and over very wide ranges and over very long time frames folks have used very high levels, 50-100ppm or more, so targeting 10-40ppm for a range should present no problems for you.
Erik 's winning AGA tank from past year's won best of show with over 100 ppm of K+ with a large stand of Ammannia and a GH of about 5 using SeaChem Eq.