Aquarium cleaner, scraper and siphon all in one. Self-priming siphon removes dirt and waste but keeps gravel in the tank where it belongs. -00 is for 5-15 gallon tanks and has a 5" reach; -01 is for tanks larger than 15 gallons and has a 9" reach. Both come with 4.5 feet of tubing; and built-in fish and gravel guards.