I came accross an infinity pool today with a basin. I've never seen one before. It's pretty interesting how it operates but what confused me was the basin. Both the pool and the basin have main drains. The homeowner belives its best to have the water in the basin low so that there is no chance that it can overflow down to the boat dock. I would have thought it's best to have it up to the tile line so that the pebbletech finish won't blister. What do you guys think?