Here is a little more info to help. pH of 7 is "neutral." pH less than 7 is acid, more than 7 is base. Each point of change of pH is ten times more than the one next to it. pH of 6 is 10 times more acid than 7, 100 more acid than 8, 1,000 times more acid than 9, and so on.
When you add limestone, it's the same as adding Rolaids. You are adding an antacid. Lime buffers the water. At the same time, lime added to acid water also adds other important dimensions...minerals for fish to build bones as well as key ingredients for plant and animal plankton growth. Plus, when there is plenty of lime to buffer the water, you don't get such wide swings of pH during daily photosynthesis and respiration of plants.


Teach a man to grow fish...
He can teach to catch fish...