My water pH is 7.3 and it should up on 8.5 - how do I do it,

[Vibsen63]

My water pH is 7.3 and it should up on 8.5 - how do I do it, so I have full control process?

[Mustafa]

There are commercial products for that. Sodium bicarbonate (baking soda) will drive the ph up, too, but only to about 8.2 in my experience. You only need tiny little amounts. Why do you need the ph that high? Even if you want to keep shrimp from sulawesi you do not need such a high ph...as long as your water is alkaline they will be just fine. Crushed coral and/or limestone will also work to *slowly* drive up your ph if your tap water does not have enough calcium carbonate (and/or sodium hydroxide). If you have hard, alkaline tap water, then just do frequent water changes with dechloraminated tap water and you will get the desired results.