1. pH – A measure of the concentration of hydrogen and hydroxide ions. The pH of a solution measures how acidic or alkaline it is. pH values range from 0 to 14. A neutral solution has a pH of 7. A pH less than 7 indicates an acidic solution while a pH greater than 7 indicates an alkaline solution.
2. The discus comes from the tributaries and streams of Amazon River, which has soft and acidic water. Thus the discus fish likes acidic water.
3. Peat is a form of dried moss usually used to soften and lower the pH of the aquarium water. The water becomes acidic.