Active vs Passive Suction: What's the Difference?

What 'active suction' means on a listing

Active suction is a general way to describe a pool cleaner that generates its own water flow. A pump inside the cleaner pulls water through a filter and sends it back into the pool. The pump is the part that creates the suction, and the filter catches the debris that moves with the water. An active machine does not need help from the pool's own circulation system.

A robotic pool cleaner is an active suction machine. It carries its own motor, its own pump, and its own filter basket, and it runs on a battery or on a cable connected to a power supply. The robot is a separate machine from the pool pump and filter, which is the point of the robotic category on this site. When you read the robotic pool cleaner buying guide, the first word in every listing title is "Robotic." That word is the signal that the cleaner is self-contained.

The phrase "active suction" may not appear on a listing at all. Sellers print the words that describe the product family: "robotic," "cordless," "power supply," "filter basket," and sometimes "wall climbing." The absence of the phrase does not mean the robot lacks a pump. Read the bullet list and the maker's page to confirm the motor and filter details.

Related articles on this site explain the parts of the pump in more detail: impeller versus vacuum suction, suction power measured in kPa, and flow rate. These articles help you read what a listing prints about the robot's pump.

What 'passive suction' means in pool cleaner terms

Passive suction is another name for a suction-side pool cleaner. This type of cleaner has no pump of its own. It connects to a skimmer or a dedicated suction line in the pool, and the pool's circulation pump creates the flow that moves the cleaner and pulls water through its debris bag or screen. The cleaner is passive because the work is done by the pool's pump, not by anything inside the cleaner.

A suction-side cleaner runs whenever the pool pump runs. Its listing would name the skimmer connection or say "suction-side" or "vacuum-side." Those words describe a different product family from robotic cleaners, and they are the most direct clue that a listing is not about a robot.

This site covers robotic cleaners only, so a passive suction cleaner is not part of the buying guides here. If a listing tells you to connect the cleaner to a skimmer or to use the pool's pump, you are reading about a suction-side product. The comparison between robots and suction-side cleaners is explained in robot versus suction-side.

Passive suction is also the term you may see in older pool-care articles or in product descriptions for suction-side cleaners. When you are shopping for a robot, you can set that term aside and look for the word "robotic" instead.

Why every robotic pool cleaner is an active suction machine

Every robotic pool cleaner is active by design. The robot has a motor that turns a pump, and the pump draws water through a filter basket. Whether the robot is cordless and battery powered or cabled to a power supply, the robot's pump does the work. The pool's pump and filter are separate equipment.

That difference is the main shopping point between a robot and a passive cleaner. With a robot, the moving water comes from the robot's own pump, so the pool's pump is not part of the robot's operation. With a suction-side cleaner, the pool's pump is the whole system. If you want a cleaner that works on its own, the product family to look for is the robot.

For a cordless robot, the battery is the power source. For a cabled robot, a power supply sits outside the water and feeds the unit through a cable. Read the maker's manual for how to place the robot in the water and how to handle the cable and power supply, and ask a licensed electrician about any installation question; UL Solutions is one organization that helps verify product compliance with applicable standards.

At the end of a cordless robot's battery life, do not put the battery in household trash or recycling bins. The US EPA recommends taking used lithium-ion batteries to separate recycling or household hazardous waste collection points, and the maker's manual carries battery-specific instructions.

How to read a listing for suction type

Start with the first word of the listing title. "Robotic" tells you the cleaner is self-contained and active. "Suction-side," "vacuum-side," or "skimmer" tells you the cleaner is passive and belongs to a different product family.

Next, read the bullet list. A robotic listing usually prints the filter basket, the brushes, and the power source. If a detail is missing, the listing simply does not state it. For example, if the title does not say "cordless," the robot may be a cabled model, or the seller may not have printed the detail. Read the maker's page for the full specification; the Dolphin pages from Maytronics and the Aiper product pages are examples of where those details appear.

Cross-check the pool type label. The title may say "inground," "above ground," or both. The robot's self-contained pump works the same way on each type, but the maker's page is where you confirm that the model is labeled for your pool. The both pool types guide explains that label in detail.

Standards such as those developed by the Pool & Hot Tub Alliance cover pool design, construction, and operation. They do not rate individual cleaners, so the listing and the maker's page are the sources for a robot's stated details.

• Listing words that describe a robotic, active suction cleaner: "robotic," "cordless," "power supply," "filter basket," "brush roller," "wall climbing," "waterline."
• Listing words that describe a passive, suction-side cleaner: "suction-side," "vacuum-side," "skimmer connection," "pool pump."

What to pick for your situation

The choice between active and passive suction is really the choice between a robotic cleaner and a suction-side cleaner. If you want a self-contained machine that runs on its own power, pick a robot. Suction-side cleaners are a separate product family, and this site does not recommend them.

For a first-time pool owner, a robot removes the question of connecting a cleaner to the skimmer and coordinating with the pool pump. For someone moving from a manual vacuum head, a robot replaces the handle and hose with a machine that carries its own pump and filter. The buying guides on this site are built around those shopping situations.

For a pool with no outlet near the water, a cordless robot removes the cable question; a cabled robot needs a power supply placed according to the maker's manual. Read the cable length on the listing if reach matters to you. The cordless robot guide and the cable length article cover those details.

What to pick for your situation

Questions

Is every robotic pool cleaner an active suction cleaner?

Yes. A robotic cleaner has its own motor and pump, so it draws water through its filter without the pool's circulation system. For shoppers comparing models, pool cleaner picks list both robotic and suction options side by side. The phrase "active suction" may not appear on the listing, but the robot's design is active.

Are passive suction and suction-side the same thing?

They describe the same product family. A passive, suction-side cleaner connects to a skimmer or a suction line and relies on the pool's pump for its suction. These cleaners are not robotic, and this site does not list them.

Do you need the pool pump running to use a robot?

A robot is a separate machine with its own motor and pump, so the pool's pump is not part of the robot's operation. Read the maker's manual for how to use the robot in your pool.

What should you look for in a listing title?

Look for "robotic" as the first word. If the listing says "suction-side," "vacuum-side," or "skimmer," it describes a passive cleaner, not a robot.

Does the word "active suction" appear on robot listings?

Sometimes, but not always. Sellers may print "active suction" or other pump words, or they may leave them out. Read the first word and the bullet list to see what the machine is.