The ankh is an ancient Egyptian symbol. It looks rather like a key. The ankh symbol was used in hieroglyphics and in designs. One of the artifacts carefully placed in King Tut's tomb was an ankh. The ankh must have meant something important to the ancient Egyptians, but we're not sure quite what that was.
You may want to look at my article HERE on lowering stabilizer. Basically if you use chlorine tablets, they have stabilizer in them and over time, can over stabilize the pool water and will need to be diluted. Also calcium levels that are high, rainfall can be a benefit to diluting the water as well.
Potassium sorbate, aka stabilizer, prevents renewed fermentation in wine that is to be bottled and/or sweetened. Use 1/2 teaspoon per gallon.. Here is a source for Potassium sorbate. It is my understanding that you use one or the other, either Campden or Potassium sorbate, not both.