PH adjusting for selective nutrition?

[WifeInTheDark]

Hi I have a few plants that i've been told have too much phosphorous, but my natural water from taps is almost 9.0!, and my ph down is 85% phosphoric acid.......see my problem? so I saw this nifty little chart;

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And i thought, If I lowered the ph to about 6.0, technically wouldn't they be able to absorb everything but calcium and phosphorous, which i can substitute the calcium from cal-mag with a foilar feed, eliminating my phosphorus toxicity?

 

[Weaselcracker]

Without being any sort of expert on the finer points of this, I think it will be tricky to make that work.
Adjusting the ph of the water in my experience doesn't mean that it stays that way long. It seems to me that generally the ph of the solution will creep upwards fairly quickly.
The other factor is the soil itself, which will affect the ph balance as well. You can't expect to pour ph 6 water in there and have it stay at 6, in my experience anyway.
Do you know the ppm of your water? And how about using a different ph down? People use various acids including sulphuric, and vinegar

 

[Serpent]

ya i seen that chart from ------------ a good web page to find some sweet info but Weaselcracker is right try other try other PH down i use PH down for the fish take works good for me,Hey if its ok for a fish it must be ok for the plants. my water in Canada is 7.0 and 200 ppm so i have good water to start with