Quote:
Originally Posted by jmontee  The reason that 4dkH water is necessary is because it has to do with an equilibrium. Deionized water that has bicarbonate added to it to a concentration of 4dKH is pH 6.6 when it has 30ppm CO2 dissolved in it. This is what makes the solution turn green. As the CO2 changes the pH changes so the color of the solution changes. If you use a 6dkH solution thyen the equilibrium point changes and a pH of 6.6 would need a lot more CO2. If you use a 6dKH soluton and push enough CO2 to make it green then you would have 45ppm CO2 which is just toxic for fish. |
That's hitting the nail on the head for me. Thanks.