I have been using a red sea drop checker for about 1 year. From reading different posts here I my be using it wrong. I called the lfs where the product was purchased with my question. The instructions said to use tank water and 2 drops of solution. I have read I should be using 4dkh, the lfs said tank water. I just want to make sure I am doing it right. Thanks
I purchased a Red Sea drop checker a few weeks ago and added tank water that registered at 4dkh. The Red Sea has worked well so far.
I move it between two planted tanks that I maintain. I use pressurized CO2 which I turn off at night. In the morning the Red Sea is blue, then a few hours later turns green. So it is registering changes in the CO2 levels in my aquarium.
I have read of several aquarists who have stated that once they add the reagent, that the Red Sea stays green all the time, even when they've turned their CO2 off at night. I have read the same complaint from aquarists using other brands of CO2 checker.
This may indicate that the tank water being used is not exactly 4dkh.
As for the reagent losing its color, after two weeks the reagent in my Red Sea is still maintaining its colors -- usually blue in the morning and green by the afternoon. I move the Red Sea between two tanks and have found that when using more aggressive CO2 3 bps in the larger tank, the Red Sea will actually turn yellow, indicating that there's too much CO2 in the water column.
When I reduce the CO2 to 1 bps the color in the Red Sea changes from yellow to green.
So the Red Sea does its job. The key is to make certain that the water used in the Red Sea is exactly 4dkh, and that the reagent is fresh. If either is off, you will not get an accurate CO2 reading.
For those who are interested in purchasing a Cal Aqua Lab CO2 checker, I was at their Website earlier, and a few of the models are back in stock.