How do i know whether i m dosing right amount of K

[Heuer]

Hi folks,

need your expert advice on this as i can't find any K test kit in the market or its going to cost a bomb.

Current dosing TMG 5ml 2x per week, Seachem Flourish Potassium 5ml 2x per week, KNO3 1/2 teaspoon 2x per week and KH2PO4 5-6 rice grain 2x per week.

Plants and fishes are doing fine but just need to know am i over dosing or under dosing K.

Fish tank : 4x2x2
vol about 95 gal.
light about 300W
KH 4
pH 6.5
about 70 small fishes main tetra.
Plants: HC, moss, nana, a. boivinanus, a. ulvaceus, sword plants, eriocaulon cinereum, hydrocotyle sibthorpiodes, hygrophila difformis, MM, red tiger lotus, rotala wallichii, tonina, val, some floating plants.

Thanks

[geoffrey]

K is hard to measure. K test kits are not available, as far as I know, here.

Majority of us just dose, without major problems, 20ppm/week with weekly 50% water change to prevent buildup. As for me, I've since lowered my dose to circa 10ppm/week but my water change is fortnightly.