I had pictures of one taken apart somewhere and will try to locate them. It consited of some PVC, electrical tape and magnets smaller than you would find on a socer moms fridge. In my loud mouthed opinion: SNAKE OIL.
It's pure junk, please don't waste your money. Spend the money on a quality skimmer instead...
From Inland Reef Aquaria:
"We decided to look into this product after a lengthy thread on the Reefs.org website where it was discussed. Our first impression was that the number and extent of the claims made for the product was totally out of proportion for what the product seemed to be.
The product explanations given on the website flew in the face of sound engineering and scientific principles. In addition, the product description seemed awfully close to numerous magnetic products sold for water purification, medical uses, and even to improve automobile gas mileage. Several of the companies selling the latter products have recently been prosecuted by the Federal Trade Commission for false claims and deceptive sales tactics. So this product raised several red flags with us, and we considered it worthy of checking out.
We ordered one from the manufacturer, and then recieved two more from hobbyists who had tried them and didn't want them anymore. We're working on several test protocols to properly investigate what, if anything, these do to the water, so please check back often as we will be updating these pages as we go. "