CO2 has an amazing ability to change the pH of the water. My tap is at 8.8 and my planted tank is around 6.6 when saturated. amazing. just a thought. I also have a KH of 5 which would make my CO2 level be around 35...¬.¬
well, needless to say, if you want lower pH, use CO2...
well, needless to say, if you want lower pH, use CO2...