All these products in most cases are a complete waste of energy and money and potentially cause a lot more harm than help. Most fish, including discus will acclimate to the natural pH of your water. The most important thing to do is frequent partial water changes, especially with discus.
I am not a scientist, but I believe based on what we know now pH is not as important as the hobby once thought it was. Keeping your ammonia and nitrites at zero, maintaining your water quality that is what is important to fish and plants.
Do not use it in planted tanks, any pH adjusters of any sort.
The main issue is KH for discus or any fish.
Since we add CO2, which changes the pH, but not the TDS/salt, or KH, this influences, pH, however, it does not affect osmoregulation of salts, which is really what fish "prefer", KH is the salt that adjust pH mostly(in most freshwater systems), so that's the one to focus on, not pH which is an indirect parameter that can be influenced by many things.
If you live in Sac, you likely have good water, low KH, American River sierra snow melt, which is about as good as it comes, low KH, high purity etc.
No need to do anything for discus other than water changes with the tap, add dechlor and that's all.
If you want plants and want to add CO2, then pH becomes irrelevant for the most part other than a gauge to measure CO2.
The KH of my tap water is about 1.2 degrees or about 20ppm.
I live in Sac.
That answers a lot of my questions. Yes I live in sacramento. I might start looking around for some discus and see if Ill be successful with them.
If you dont mind me asking, how does ph measure co2? im new.