[I've been using it with great success for over a year.
My 29g uses 20ml of each part every day. You are supposed to add it in the morning when your pH is lowest, but that doesn't fit my schedule, so I always at it at night after lights are out.
At first, you will need to test your tank daily to get the right amount figured. You want your alkalinity at 8-11 dKH, and your Calcium at 400-450ppm.
Mine is at 9.6 and 420 respectively last weekend. Time for another test.]