Nevermind... disregard. I asked a dumb question and then couldn't figure out how to delete it.
Right, so regardless of the ph in the tank, the kh within the dropper should be set at 4!? so basically kh=4 is universal?the distilled water and baking soda should have a KH of 4. If they have a KH of 4, then your readings of co2 will show green at 30 ppm.
1) Turn drop checker upside down and place 5 drops of reagent inside the checker.
2) With a pipette (not included) add tank water to drop checker so that it's half full of water.
3) Turn drop checker over carefully (without spilling contents) and place inside aquarium so that it is visible.
4) Within 1 hour drop checker will display a reading according to your C02 levels. Green is the ideal colour, yellow is too much C02 and blue is too little (adjust C02 output accordingly)
5) After each water change, renew reagent in drop checker by following directions above
That was taken from here http://www.aquaticplantcentral.com/forumapc/aquarium-equipment/38343-co2-drop-check-how.htmled seeley said:Just add the 4dKH solution to the drop checker, add the indicator solution and then turn it over and submerge so the solution can't mix with the tank water. As Muirner said, the CO2 in the water will come out of solution into the air space in the drop checker and will then dissolve into the solution in the drop checker so that the level of CO2 in all three are the same. When this is 30ppm that will turn a 4dKH solution green. The fact that the CO2 has to get out of solution into the air space then back into solution in the drop checker solution means there is a time lag in the colour change.
According to this one person on ebay, they say use tank water...
Ok so what happens when you run out of pH indicator solution? Can you order refills or just use a standard pH test kit?
^^Guys - Read #42 above.^^I have 2 different indicators, one is from RedSea and the other 2 are from Azoo. Both state in their directions to use tank water in the units and add the reagent to it. I have done it this way the entire time that I have had them and I have found them both to be very reliable. For the most part, the reagent reacts for anywhere from 1-2 months for me, but I usually like to clean out the indicators every other month or so or else I find they can build up with slime or other stuff. Just adding my 2 cents to the thread. :-D
Turbomkt - Right. pH/KH charts are not as accurate because KH is a measure of (just) carbonate hardness. Your tank has sources other than carbonate contributing to hardness, but your test kit for hardness can't discern carbonate hardness from all other possible sources of hardness, so it's not that accurate. Even if it were accurate, all you get is a point in time reading. You can't spot trends without a lot more testing. Drop checkers may be a little behind in terms of time, but where things have been vs. where they're going is quite valuable information (and they're more accurate than charts unless you have aquarium water that is unusually devoid of ion sources).I can see how tank water will give you your pH, which you can couple with KH (not an exact measurement like known KH solution) but I doubt that it's anywhere close to as helpful as the known KH method. Known KH is literally "read the color and know your CO2 level as low, high or just right".
I have read this topic with much interest.the distilled water and baking soda should have a KH of 4. If they have a KH of 4, then your readings of co2 will show green at 30 ppm.
4) What are the exact ingrediënt of dKH water?.... it's 4dKH water (RO/DI & a trace baking soda).....
No. Unless you want to completely control the kh of your system and/or need softer water to grow the few 'soft water' plants.Is it necessary to use RO water (not pure) in my fish tank?
Nothing wrong with that.In my fish tank the dKH=8.
You can use the drop checker to measure your CO2 values, IF you use kh4 water in your drop checker.Can I use this test to see my co2 value is right?
You need water with kh4 for your drop checker.Do I need an other dKH value in my tester?