I think the water is fine for brewing.
It seems like you might want to stick around an SRM of 20 to 25.
If you nail your mash water with like 3ml of lactic acid and your sparge water with 4ml you should be able to mash something along the lines of 10 to 15 SRM.
If you use 33% distilled water for your mash then you should be able to hit the 17 to 20 SRM range just fine.
Here, I am assuming you mash with 3 gallons and sparge with 4 gallons.
google the ezwatercalc website.
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