Robotic, Suction or Pressure: Which Kind of Pool Cleaner Do You Need?

A suction-side cleaner plugs into the skimmer or a dedicated suction port with a long hose. The pump's suction drags it around the pool, and everything it picks up travels down the hose into the pump basket and then the filter. It has almost no moving parts of its own, which is why it is the cheapest to buy, and why it only works while the pump runs.

A pressure-side cleaner connects to a return line instead and uses the water being pushed back into the pool to drive its wheels and create a venturi that lifts debris into a bag it tows. Many need a separate booster pump to have enough pressure. The dirt stays in the bag rather than going to the filter, which is its main advantage over suction-side designs.

A robot is a self-contained machine. A low-voltage power supply on the deck (or a battery inside it) runs its own drive motors and pump, and it filters the water through its own basket or cartridge. It needs nothing from the pool's plumbing, and it can run while the pump is off.

The honest answer to whether a robot is worth it next to a working pool filter is that they do different jobs. The filter cleans water that passes through it; it cannot pick up the silt and leaves that have already settled on the floor. Something has to go and get those, and the choice is a brush and a manual vacuum, a pump-driven cleaner, or a robot.

Because a robot filters its own water, the pool filter sees less debris and needs backwashing or cleaning less often, and the pump does not have to run for the cleaner's sake. On an older single-speed pump, that is the part of the running cost a robot actually removes.

This catalog covers robots only — 46 floor robots and 6 surface skimmers — because suction and pressure cleaners are bought on different grounds entirely: they are cheap, simple and dependent on the pump, which is exactly the trade a robot exists to avoid.

If the pool already has a dedicated cleaner line and a booster pump, a pressure-side cleaner uses equipment that is already paid for. If the budget is under the price of the cheapest robots here and the pool is small and lightly used, a suction-side cleaner does the floor adequately. And in a pool with heavy leaf fall, a pressure-side cleaner's large bag can hold more than most robot baskets — though a surface skimmer robot catches those leaves before they sink at all.