The polarization helps to cut glare and the tint helps to improve contrast. Let your eye roam over the bottom, looking keenly every time it encounters an elongate form. Fish move in an unpredictable manner. They may dart to one place, then go deep, then slide over and hold behind a piece of cover. Always be watchful for any such erratic motion, even if very slight.
Color plays a role in spotting fish as well.
Although even the clearest water will dull and distort colors somewhat, the crimson stripe of a rainbow, the white and orange belly of a brookie, and the even the pewter back of a tarpon are easily spotted by a watchful angler. Conversely, the absence of all color, in the form of a shadow, can provide what is sometimes the biggest clue to a fish's whereabouts. A shadow stands out against nearly all bottoms, allowing an angler to follow a fish's movements even through wind or current ruffle. Often, the tip-off to a fish's presence is not anything obvious, but rather a cue as subtle as the sliver of white of a fish's mouth as it breathes or feeds. Another similar clue is the flash of a fish's flank as it turns to feed or change direction.