Skimmer Connection or Dedicated Line: Which Is Better for Your Cleaner

How suction cleaners connect to your pool

A suction-side pool cleaner is powered entirely by the water flow created by your pool's main circulation pump. The pump draws water through the cleaner's inlet, carries it up the hose, and pushes it through the filter before returning it to the pool. That means the cleaner must connect to the suction side of the pump, where the pump is pulling water from the pool.

Most residential pools have two or more suction points: the skimmer(s), which pull water from the surface, and one or more main drains at the bottom. Many in-ground pools also include a dedicated suction line, a separate pipe that runs from a wall fitting on the pool floor or lower wall directly to the pump. A suction cleaner can attach to either a skimmer or a dedicated line, and the choice affects how the cleaner moves, how much suction it gets, and what else happens in the pool while it runs.

The industry guidance from the Pool & Hot Tub Alliance (PHTA) is that skimmers are the standard surface-water intake for residential pools. Dedicated suction lines are a design option that some builders include, often in pools where the owner wants to run a cleaner without giving up skimming. Understanding how your pool is plumbed is the first step in deciding which connection to use.

• Skimmer connection: the cleaner hose attaches to a vacuum plate that fits into the skimmer basket opening.
• Dedicated line connection: the hose attaches to a wall fitting that is plumbed directly to the pump suction.
• Both methods use the same pump, filter, and circulation system.

Pros and cons of a skimmer connection

Connecting a suction cleaner to the skimmer is the most common method for in-ground pools, and it is also the way most above-ground pools are set up. You seat a vacuum plate (also called a skimmer plate) into the skimmer opening, attach the cleaner hose to the plate, and the pump draws water through the cleaner just as it normally draws water through the skimmer.

The biggest advantage is convenience. The skimmer is already there, so there is no extra plumbing to install and no wall fitting to add. You can disconnect the cleaner and go back to normal skimming in seconds by lifting the plate out. For pools with a single skimmer, this is the only option without a costly plumbing change.

The main drawback is that while the cleaner is running, the skimmer cannot do its normal job of pulling debris off the surface. Anything floating on the water waits until the cleaner is done. In addition, the cleaner hose occupies part of the skimmer's opening, which reduces the water flow available for surface skimming even if some flow still passes around the plate.

Another consideration is that skimmer connections can throttle the amount of suction the cleaner receives. The skimmer opening and the vacuum plate are designed to let water flow, but the plate's narrow connection can slightly reduce flow compared to a dedicated line. With a properly sized pump and clean filter, this is rarely a problem, but it is a factor for owners who run their pump at very low speeds.

Pros and cons of a dedicated suction line

A dedicated suction line is a separate pipe that runs from a wall fitting in the pool to the pump, independent of the skimmer and main drain. In-ground pools with this feature typically have the fitting on the pool floor or on a lower side wall, and a valve in the equipment area lets you control the flow to that line.

The primary benefit is that you can run the cleaner and still skim the surface at full capacity. This is useful if your pool is surrounded by trees and you need continuous surface cleaning. A dedicated line also lets you isolate the cleaner's suction: you can close the skimmer valve and open only the dedicated line valve, sending the pump's full suction to the cleaner, which can help the cleaner climb walls and pick up debris.

The drawbacks are fewer but significant. Not every pool has a dedicated line, and adding one requires cutting into the pool shell and running new plumbing to the equipment pad. That is an invasive and potentially expensive project that is best done during a renovation. Even when a dedicated line exists, it adds another valve to adjust and another possible point of air leaks or flow restriction.

A dedicated line also means the cleaner has its own path to the pump, which can be a benefit if the skimmer is far from the pump and the hose would need a very long run through the skimmer. The wall fitting itself is usually at the deep end or the center of the pool, which can be convenient for hose routing compared to a skimmer in a corner.

For pools with a dedicated line, many owners prefer to use it for periodic deep cleaning sessions and use the skimmer connection for quick touch-ups. Some suction cleaners come with both connection options, or with an adapter that fits the wall fitting.

Performance and pump flow

The performance of a suction cleaner depends on water flow, not just on which connection you use. The pump must deliver enough flow to the cleaner to keep it moving and picking up debris. ENERGY STAR notes that filtration requires only half the flow rate of running a pool cleaner, so you may need to run the pump at a higher speed while the cleaner is working.

With a skimmer connection, the cleaner shares the skimmer's flow with whatever surface water the skimmer still pulls. With a dedicated line, you can close the skimmer valve and direct all suction to the cleaner, maximizing the flow it receives. This can make a difference on long hose runs or with cleaners that need strong flow to climb pool walls.

Variable-speed pumps make this easier: you can program a higher speed for cleaning cycles and a lower speed for normal filtration. ENERGY STAR says reducing pump speed by one-half allows the pump to use just one-eighth as much energy, which is why running the pump at the minimum speed needed for the task matters. See the guide on matching your cleaner to pump flow and the page on flow rate basics for more context.

The length and diameter of the hose also matter. A longer hose reduces flow due to friction, so the connection point that gives the shortest, straightest hose path usually delivers the best performance. A skimmer in a convenient location can beat a dedicated line on the far side of the pool.

Plumbing and installation considerations

If your pool already has a dedicated suction line, using it is usually a matter of connecting the hose and adjusting the valve. If it does not, adding one is a major project: it involves draining the pool, cutting an opening in the shell for the wall fitting, and running a new pipe from that fitting to the pump suction. That is well beyond a weekend DIY task for most owners.

A skimmer connection requires no new plumbing at all. You only need a vacuum plate that matches your skimmer's opening, and most suction cleaners include one or it is available separately. Above-ground pools also use a skimmer or an adapter that fits the pump inlet, so for those pools the skimmer-style connection is the standard.

If you are considering a new pool build, you have the option to include a dedicated suction line from the start. That is the cleanest way to get a dedicated line without retrofitting. Discuss the cleaner type you plan to use with your builder so the plumbing, including pipe size and valve placement, matches the cleaner's requirements.

For existing pools, the decision is almost always between using the skimmer and accepting its limitations, or making a large plumbing modification. For most owners, the skimmer connection wins by default because it is free, reversible, and requires no drilling or repiping.

Which cleaner types use each connection

Suction-side cleaners are designed to work with either a skimmer or a dedicated line, though individual models may specify one or the other. The hose connects to the vacuum plate in the skimmer or to the wall fitting of a dedicated line, and the cleaner body is identical in both cases. Many new suction cleaners include a connector that fits both a skimmer plate and a standard wall fitting.

Pressure-side cleaners use a separate return line and a booster pump, so they do not connect to the skimmer or a suction dedicated line at all. Robotic cleaners are self-contained and powered by low voltage from a transformer, so they do not use your pool's plumbing for cleaning. ENERGY STAR notes that robotic cleaners draw power from a wall outlet rather than the pump, which is why they use far less energy than pump-driven cleaners. See the robotic vs suction vs pressure comparison for a fuller picture.

If you are shopping for a suction cleaner, check the manufacturer's instructions for the recommended connection. Some cleaners are sold with a vacuum plate sized for a specific skimmer brand, and some wall fittings have a proprietary shape. This is especially relevant for above-ground pools, where the connection is often through the pump inlet rather than a skimmer. The installation guide covers more setup details.

How to decide for your pool

Start by checking whether your pool has a dedicated suction line. Look for a wall fitting that is separate from the skimmer and main drain, and check the equipment pad for an extra valve that controls that line. If you have one, you can use either method, and the choice depends on your priorities.

If you want to maintain full skimming while the cleaner runs, and you have a dedicated line, use the dedicated line. This is the scenario where a dedicated line clearly outperforms a skimmer connection. If you want the simplest setup, the fewest valves to manage, and you do not mind pausing surface skimming during cleaning, use the skimmer connection.

If your pool only has a skimmer and a main drain, the skimmer connection is your only practical option for a suction cleaner, short of adding a dedicated line at substantial effort. Most pool owners fall into this group, and it works well as long as the pump delivers enough flow and the hose is the right length.

For above-ground pools, the skimmer or pump-inlet connection is the standard approach. The hose setup is similar, and the main difference is that the vacuum plate may be optional if the pump has a built-in strainer basket you can attach the hose to. The above-ground vs in-ground comparison explains how the two pool types differ.

Practical tips for either connection

Whichever connection you use, a few practices keep the cleaner working well. Prime the hose before attaching it: submerge it to fill it with water so air does not cause the pump to lose suction. Check the pump's strainer basket regularly, because debris that bypasses the cleaner can clog the impeller.

Monitor the pump pressure. A significant change on the filter pressure gauge, whether higher or lower, often indicates a blocked skimmer, a clogged hose, or a dirty filter. Clear the obstruction before running the cleaner for a full cycle.

If you use a skimmer connection, make sure the vacuum plate seals well enough that you do not draw air into the system. An ill-fitting plate can cause the pump to lose prime and the cleaner to stall. The skimmer vacuum plate installation page walks through the proper fit.

For a dedicated line, operate the valve so that you do not starve the pump. Closing the skimmer valve completely while the cleaner runs is usually fine, but you still need the main drain open if your pump pulls water from both. Adjust valves gradually and watch the pump's suction to avoid air entrainment.

What to pick for your pool

Questions

Can I connect a suction cleaner to a skimmer and a dedicated line at the same time?

No. The cleaner hose attaches to one suction source at a time. The other source remains open for normal suction, but the cleaner only draws water through the connection it is plugged into.

Does a dedicated line give a suction cleaner more power?

It can. With a dedicated line, you can close the skimmer valve and direct the pump's full suction to the cleaner. The cleaner receives more flow than it would when sharing the skimmer, which can improve wall climbing and debris pickup, assuming the pump has enough capacity.

Can I convert a skimmer connection to a dedicated line?

Converting requires adding a new suction line, which involves cutting into the pool shell and running new plumbing to the pump. It is a significant renovation. For most owners, the skimmer connection is sufficient.

Do robotic cleaners use a skimmer or dedicated line?

Neither. Robotic cleaners are self-contained and powered by low-voltage electricity from a transformer. They collect debris in a built-in filter and do not rely on the pool's pump or plumbing. ENERGY STAR notes that robotic cleaners use far less energy than pump-driven cleaners.

Will connecting to the skimmer hurt my pump?

Not if the connection is tight and the vacuum plate fits properly. An air leak from a poor seal can cause the pump to lose prime, so check the seal before running the cleaner.

Is a dedicated line worth the cost if my pool doesn't have one?

For most pools, the skimmer connection delivers acceptable performance, and the expense and disruption of adding a dedicated line are hard to justify. If you are building a new pool, including a dedicated line is a reasonable option.