i used this to make my solution but when i tested the KH just to be sure,it changed on the first drop clearly since it changed from yellow to blue.When you add more drops it justs turns darker .so in essence its a 1dkh where it should be 4
Dissolve 1 tsp (6 grams) of sodium bi-carb into 1 litre of distilled water.
Take 10mL of this solution and dissolve it further into 490mL of distilled water.
You now have a solution with carbonate hardness of 4 degrees.
This can be used in a drop checker to estimate visually what the concentration of CO2 is in your aquarium water.
You can store the remaining solution in an air tight container out of direct sunlight for several months
Dissolve 1 tsp (6 grams) of sodium bi-carb into 1 litre of distilled water.
Take 10mL of this solution and dissolve it further into 490mL of distilled water.
You now have a solution with carbonate hardness of 4 degrees.
This can be used in a drop checker to estimate visually what the concentration of CO2 is in your aquarium water.
You can store the remaining solution in an air tight container out of direct sunlight for several months