I agree with you that that magnesium acts as an inhibitor of crystallization of calcium oxalate calculus , in addition to citrate & pyrophosphate . Though hypercalciuria occurs with hard water , it is difficult to prove that this is the mechanism , unless the role of the inhibitors are evaluated . The risk factors for calcium stones are hypercalciuria , low urine volume , hypocitraturia , hyperuricosuria & hyperoxaluria . I recommend that urinary magnesium should also be included . Randomised trials in idiopathic calcium oxalate nephrolithiasis have revealed that 1) Increasing water intake to raise urinary volume to more than 2 litres per day ( risk reduction [rr] : 55% ) .2) Hydrochlorothiazide in a dose of 25-50 mg ( rr :54% ) 3) Allopurinol in a dose of 100 mg tid (rr: 45% ).4) Potassium-magnesium citrate in a dose of 42 / 21 / 63 mEq ( rr 81%). 5) Potassium citrate in a dose of 30-60 mEq ( rr :65% ) are therapeutic modalities which have shown beneficial reduction in recurrent stone formation . Magnesium hydroxide in a dose of 650-1300 mg has not shown any reduction , while potassium magnesium citrate has shown the maximum benefit . Reference : Manual of Nephrology by Robert W.Schrier ( fifth edition) - ' The Patient with Renal Stones ' by Robert . F. Reilly.

I feel that magnesium disorders are neglected & needs more studies to establish its importance .

Thank you very much Singh for your answer. you are right. Magnesium disorders are really neglected. If you have other documentation will you please share it with me. I am working about the effect of water hardness on health. I've read from literature there is a relationship between water hardness and various diseases such as urolithiasis, cardiovascular diseases, osteoporosis.