Has anyone tried Easy-Life Potassium Test kit or any K test kit out there?

[Allan Asis]

I'm OCD when it comes to testing parameters so here I am hunting for the next test kit to invest in.
I saw http://www.aquaessentials.co.uk/easy...it-p-7118.html easy-life test kit in C328 today and ii'm wondering if anyone uses this and how reliable this kit is?

[Xiaozhuang]

Just a note on test-kits; many of them need to be calibrated by mixing your own test stock solution to compare against. Some like GH test kits expire faster than others, others like hobbyist level CO2/O2 test kits have innate wide error ratios (this includes drop checkers). Also the needs of a tank range quite widely; plant a lot of hygrophilas and you may need to dose a lot more potassium than a tank with say mostly java fern. So while you can test to see if you're in the ballpark, ultimately you have to read the plants to see what is required.; fine tuning would come from that angle. Ratios of NPK don't matter as much as plant response. Some tanks do fine with 20ppm nitrates, 0.1ppm phosphates, others might do much better with say 15ppm nitrates, 5ppm phosphates, as plant selection changes, and plant mass grows, dosing needs change accordingly as well. I've seen plenty of tanks where levels seem perfect using say EI (estimative index), but the plants still don't do well/or algae abound.

You can test to augment your knowledge/understanding of your tank parameters, but I would suggest a better investment is to have a regular dosing schedule that you keep good record of, and watch plant growth closely while tweaking/experimenting with various parameters. And becareful of the false positives that test-kits give.

cheers,
Xz

[Allan Asis]

Just a note on test-kits; many of them need to be calibrated by mixing your own test stock solution to compare against. Some like GH test kits expire faster than others, others like hobbyist level CO2/O2 test kits have innate wide error ratios (this includes drop checkers). Also the needs of a tank range quite widely; plant a lot of hygrophilas and you may need to dose a lot more potassium than a tank with say mostly java fern. So while you can test to see if you're in the ballpark, ultimately you have to read the plants to see what is required.; fine tuning would come from that angle. Ratios of NPK don't matter as much as plant response. Some tanks do fine with 20ppm nitrates, 0.1ppm phosphates, others might do much better with say 15ppm nitrates, 5ppm phosphates, as plant selection changes, and plant mass grows, dosing needs change accordingly as well. I've seen plenty of tanks where levels seem perfect using say EI (estimative index), but the plants still don't do well/or algae abound.

You can test to augment your knowledge/understanding of your tank parameters, but I would suggest a better investment is to have a regular dosing schedule that you keep good record of, and watch plant growth closely while tweaking/experimenting with various parameters. And becareful of the false positives that test-kits give.

cheers,
Xz

Thanks for the feedback!
Yup, I use RO/DI water as base reference to compare when testing parameters. My purpose for testing water parameters is to know plants' nutrient uptake.

And I agree with you completely! In my short experience with planted tanks, it seems the best way to measure if you are in the right direction is by looking at the plants. There's one time where all my plants are looking very healthy except hydrocotyle tripartita. Then I realized that this plant needs a lot more phosphorus than other plants so I went to dose more phosphorus (way more compared to recommended NPK ratios I see on the internet) and in a week the plant recovered and at this point it has grown very thick and bushy while phosphate levels remain at 0ppm most of the time.
There's also another incident where I noticed a huge spike of nitrate level out of nowhere. Then I remember pulling out water wisteria a week before that huge spike and realized that plant is a huge sucker for nitrates lol!

In the end it all comes down to what plants you have and knowing their specific needs and being able to respond to their behavior. Being very new to this hobby, testing the parameters help me narrow down possible causes or nutrient spikes and deficiencies and how to handle them.

[Xiaozhuang]