I bought one of these test kits. it is the only freshwater K test kit I found. It is the only one in the proper range as well. The first one didn't seem to work right. It was backwards from what the color card said. On the card, 0 K gives a dark brown and high K gives clear or light yellow. After various tests on tap and tank water with and without K added It seemed backwards so I contacted them and they sent me a new kit.
I received a lot of free goodies and 2 brand new K test Kits from Easy Life.
The seals were broken on one which I assume they tried it themselves before sending it out to replace a bad kit. So I assume it worked right for them. I used that same one.
I ran the following tests:
Tested tank water, got bright yellow color. Perhaps 17 ppm according to chart which only shows a weak yellow as an option.
Tested sink water dechlorinated with activated carbon block filter. Same 17 ppm. Suspicious but possible.
Tested RODI water and got darker color. About 5 ppm at best. Should have been 0 ppm but I would accept is as close enough. it would be OK as long as I know that is what happens at 0 ppm.
Tested RODI with 2 drops of Flourish Potassium Added to the 2 ml sample of tank water. Should have been clear but got light green color. I am sure it is just too much for the test to read properly. Lot's of color test malfunction at overdose levels.
I decided that so much K was probably throwing off the test and causing the green color. I decided to add some K to my tank then retests. I used 5 ml of Flourish Potassium to about 15 gal of actual water. I let it stir for 20 minutes with the pumps. I retested.
Before I got a bright yellow color. This time I should have got very clear. I got the yellow color again but it was slightly more clear.
I conclude that the chemicals are actually working this time. I just think the color card isn't very good. I supposed a person could make some standard K solutions to use instead. I think the test would be accurate with that method. Making all those Potassium standards is a pain though. A person could could probably make there own color chart of they did go to all the trouble of making the standards.
I have asked the company to advise me if there are any ions that might be causing interference or if my method is wrong. I am following the instructions of course.
I would like to say that even though the color card sucks this company has gone through great lengths to try to make me happy. When I advised them of the problem they shipped out a new kit immediately. They are in The Netherlands and I am in the US. It came back so they reshipped with a different carrier. It came back to them again. They shipped a 3rd time with upgraded service and it finally got through. They gave me some nice bottles of ferts and liquid Carbon. They gave me 2 replacement K test kits as well. They have been good at answering my email. All this must have been a lot more then what I paid for the Kit so I am not asking for a refund. I am happy with what they did for me. I hope they get the color card worked out. For those of you who really want a working K test for your planted tank I would still buy this product if I had the skills to make standard solutions and a color card. It would be cheaper then a 200$ colorimeter etc. You could also just eyeball it and know about where you were. Close enough is good enough with K. Just to tell you weather you had any K in your water or not.
I received a lot of free goodies and 2 brand new K test Kits from Easy Life.
The seals were broken on one which I assume they tried it themselves before sending it out to replace a bad kit. So I assume it worked right for them. I used that same one.
I ran the following tests:
Tested tank water, got bright yellow color. Perhaps 17 ppm according to chart which only shows a weak yellow as an option.
Tested sink water dechlorinated with activated carbon block filter. Same 17 ppm. Suspicious but possible.
Tested RODI water and got darker color. About 5 ppm at best. Should have been 0 ppm but I would accept is as close enough. it would be OK as long as I know that is what happens at 0 ppm.
Tested RODI with 2 drops of Flourish Potassium Added to the 2 ml sample of tank water. Should have been clear but got light green color. I am sure it is just too much for the test to read properly. Lot's of color test malfunction at overdose levels.
I decided that so much K was probably throwing off the test and causing the green color. I decided to add some K to my tank then retests. I used 5 ml of Flourish Potassium to about 15 gal of actual water. I let it stir for 20 minutes with the pumps. I retested.
Before I got a bright yellow color. This time I should have got very clear. I got the yellow color again but it was slightly more clear.
I conclude that the chemicals are actually working this time. I just think the color card isn't very good. I supposed a person could make some standard K solutions to use instead. I think the test would be accurate with that method. Making all those Potassium standards is a pain though. A person could could probably make there own color chart of they did go to all the trouble of making the standards.
I have asked the company to advise me if there are any ions that might be causing interference or if my method is wrong. I am following the instructions of course.
I would like to say that even though the color card sucks this company has gone through great lengths to try to make me happy. When I advised them of the problem they shipped out a new kit immediately. They are in The Netherlands and I am in the US. It came back so they reshipped with a different carrier. It came back to them again. They shipped a 3rd time with upgraded service and it finally got through. They gave me some nice bottles of ferts and liquid Carbon. They gave me 2 replacement K test kits as well. They have been good at answering my email. All this must have been a lot more then what I paid for the Kit so I am not asking for a refund. I am happy with what they did for me. I hope they get the color card worked out. For those of you who really want a working K test for your planted tank I would still buy this product if I had the skills to make standard solutions and a color card. It would be cheaper then a 200$ colorimeter etc. You could also just eyeball it and know about where you were. Close enough is good enough with K. Just to tell you weather you had any K in your water or not.