A host of culprits conspire to make your pool dirty. Some are obvious—leaves, dirt, and bugs, for instance. Others are subtle and tend to sneak up over time.

Even if the surfaces of the pool—the sides, floor, steps, and tiles—look clean, they should be brushed at least every other week to clean away debris that quietly and almost invisibly accumulates such algae and mineral buildup. Be particularly careful to clean the “scum” line, where scale buildup can become an unsightly problem. If brushing doesn’t remove a line that’s starting to form, try using tile cleaner.

Recent innovations in pool-cleaning devices make sweeping, vacuuming, and scrubbing the pool less of a chore. But the old standby, the long-handled skimmer net, is a good tool for removing the big, easy-to-reach debris so that your filtration system doesn’t have to deal with it.

Suction tools
These attach to your pool’s filtration system—usually to the skimmer—and borrow power from the pump to suck dirt and debris off the bottom of the pool, directing it toward the filter. Some models look like a long wand that you manually use to vacuum the floor and sides of the pool.

Pressure tools
These use the return pressure supplied by the pool’s main pump or by a secondary booster pump to dislodge dirt from the sides and bottom of the pool. Usually the filter will eventually capture the debris, but some devices have their own debris collection bags.

Robotic devices
These units operate independent of the pool’s pump system. They are controlled by an internal computer and run on battery power. They have their own pump to supply suction power, their own filter, and their own debris collection bag. They are the ultimate in convenience. Simply drop them in the water and let them do the work. Prices vary quite a bit. Some of the inexpensive models are getting good reviews, though the high-end products are more powerful and durable.

Built-in cleaning system
You’ve probably noticed high-pressure jets in public pools. Part of an in-floor cleaning system, these built-in jets are options that homeowners can choose, too, when building a pool. They typically add several thousand dollars to the cost of the pool, but if you can afford it, they are worth the expense because they are very effective and make it much easier to keep a pool clean. Located where dirt and scum accumulate, the jets rotate and loosen debris before it has a chance to build up and direct it toward the pool drain, forcing it to travel through the filtration system.