Alkaline (9.6) water, top-dressing treatment

I recently discovered our tap water is ridiculously alkaline at about 9.6 ph.
We live in central Tx, and have had to water excessively to keep everything alive through the drought. Many of our trees are showing chlorosis, and burned leaf tips, and other signs of nutrient deficiency.
I have started treating the tap water with pH down to get it around 5-6, which works for some of our smaller and more sensitive trees, but is not scalable for gardens and larger trees in development.
A large water collection or conditioning system is not a workable solution right now.

I am looking for top-dressing solutions, that can treat the alkaline tap water when it is applied, without overly acidifying rain water:

  • We are top-dressing with acidic compost (citrus peal and coffee grounds)
  • @e are Trying gypsum, currently in very small amounts

How safe is gypsum? I am hesitant to use more than a small sprinkle
Are there better options?

I know you said large scale water conditioning is not an option, but it can be done fairly easily and cheaply. I use a 3/4" Mazzei venturi fertilizer injector between the faucet and hose to bring my water down from pH of 8. I use phosphoric acid (pH Down) that is diluted to an appropriate concentration in a 5 gallon bucket as the feedstock (acetic acid - vinegar is another good option). This system has an adjustable injection rate so you have to play around a bit get the right rate and acid concentration, but once you have it set it seems to be fairly stable. At some point I may upgrade to one of the more precise systems, but for now this works well for about $70 including shipping and the plumbing fittings.


Thanks @MartyWeiser

We can consider an injector system.
We currently have a single always-on tap, that feeds a splitter, the splitter feeds 1 blumat system behind a pressure regulator, 2 sprinklers on timers, and a watering hose. It looks like the sprinklers and hose will work just fine, but the blumat system may be a problem.

Do you know if the constant back-pressure, when the valves are closed and just the blumat is on will be a problem?

From a quick glance, it looks like getting treated water to the blumats would require a more complicated bypass system, so, it may require setting up two injectors.

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I do not know how the constant back pressure will impact the system. Their website Mazzei | Mazzei Injector | Leader In Mixing & Contacting Technologies does list drip irrigation as an application so you can dig in and/or ask them some questions.