Dolphin Quantum

Powered Brushes. Dolphin marks the Quantum's two brushes as active, which means they are powered and turn on their own instead of only following the robot. Among the Dolphins in our Pro tier, that puts it ahead of the Premier and the Sigma, whose combined brushes are not driven. Its suction is rated at 4,000 gallons per hour, which is lower than those two. Which matters more depends on your pool, since a powered brush may help on walls with a clinging film, while stronger suction may help more with loose debris.

Filters In The Box. A fine filter kit is fitted, and an ultra-fine kit ships with it as an additional filter, so you can switch to the finer one when pollen or dust is in the water. The basket lifts out through the top, so the robot stays the right way up while you empty it. Dolphin gives no micron figure for either kit.

Weekly Timer. A weekly timer on the power supply repeats the two-hour cycle every day, every other day or every third day. There is no delayed start, no remote and no full-filter indicator, so checking the basket after each run is up to you. Each schedule runs for one week, after which you press the timer button again to set the next one. If you would rather schedule cycles from your phone, the Dolphin Explorer E50 is the one to look at.

Cable Swivel. An anti-tangle swivel lets the robot turn on the walls without winding the cable into knots, which matters on a corded robot that climbs. Dolphin's US spec sheet gives no cable length, though, so measure from your outlet to the far end of the pool before you buy.

Weight And Pool Shapes. At 18.3 pounds, the Quantum is lighter than the Premier or the Sigma, so lifting it out at the end of a cycle is a little easier. Maytronics lists rectangular, round, free-form and kidney shapes, in both inground and above-ground pools.