Hard seltzer convinced a generation of drinkers that pounding six cans was basically fine. Low-calorie, low alcohol, it’s practically a health decision. Nephrologists are less enthusiastic. Researchers at Hackensack Meridian Jersey Shore University Medical Center have identified a new disorder tied specifically to excessive hard seltzer consumption. It’s called Mehandru/Vachharajani Syndrome—only the second newly identified kidney disorder in th…