So if you have a PH of 8.5 and an alk of 280 from your tap, and you want to bring it down. How would a hydro grower go about this? The reason I ask is in some situations the alkalinity will cause the PH to rebound a while after you add acid. so you bring it down to 7 and an hour later it is back up at 8.0. The proper balance for PH and alk is a PH of 7 and an alk of 80-100 to prevent the alkali particles(carbonates) from interacting with the hydrogen ions(acid). An acid demand test will help but they are not very accurate. This is assuming the nutes are PH ballanced The point is that you have to look at alkalinity when looking at PH as they are related and move together, and high akl can cause a false lower PH reading after adding acid. This is why I dont bother with PH, it takes to long. What do others do or is this not really an issue?
280ppm from the tap, use RO water, it's just that simple... There are other environmental factors which influence pH swing.. Even if you water is good, if the plant's environment is not, you still will get a pH swing... Not checking pH in hydroponics is not a smart thing to do... Also, pH for hydroponics should be 5.5 to 6.0 with the target being 5.8.