Maintaining KH level (alkalinity) in a tank will also be challenging. The traditional method of alkalinity measurement is to combine an acid such as HCL with a sample solution of tank water. And record the change of PH values before and after the blending. The alkalinity of the water sample is then obtained as a serve as of PH value changed, and the quantity of acid added. It is a complex and time consuming process that you might have to accomplish over and over again.