Watch this video to learn what it means when you get large bubbles in the pool when your solar pool heating system starts up each time.

When your pool pump shuts off or your solar panels shut off during the day, the water in the panels drains down to the pool. The panels fill up with air. When your solar pool heater starts up, the air is purged from the panels and forced back to the pool through your pool jets. Eventually, the large bubbles should stop.