"Think of the stress melting away," Greg told his wife, Sarah, as he signed the installment plan. "Think of the winter nights under the stars."

The "paradise" began to smell less like a spa and more like a public pool that had seen better days. Greg spent his Saturdays hunched over the water like a mad scientist, clutching test strips and bottles of pH-Down.

The novelty had evaporated. The kids were bored of it. Sarah didn't want to ruin her hair. Greg was tired of the ritual: the freezing dash from the back door to the tub, the wet footprints on the hardwood, and the constant battle against the local raccoon who viewed the insulated cover as a very warm, very expensive bed.

"The alkalinity is spiking, Sarah! I can’t stabilize the calcium hardness!" he shouted, his eyes red from chlorine fumes. The "Zen" was gone, replaced by the crushing responsibility of keeping a giant vat of human soup from turning into a swamp.