Dolphin S100 review

The Dolphin S100 (Product No. 99996121-USF) is a corded cleaner listed for floor-and-wall work in pools up to 33 feet, with a two-hour default cycle, weekly timer, top-access combination filter kit, and an additional Ultra-Fine Filter Kit in the box. Maytronics classifies this exact U.S. listing for in-ground and above-ground pools and lists rectangular, round, free-shape, and kidney shapes. This is a source-based assessment, not a poolside trial; it does not establish performance on a particular finish, step, or layout.

A compact rating, not a universal pool-fit promise

The manufacturer’s 33-foot maximum is the most useful first screen. The listed coverage is floor and walls, while the formal specification table marks waterline scrubbing No. A pool longer than 33 feet or a requirement for waterline cleaning is therefore a poor match on the available evidence. The table lists both in-ground and above-ground classifications and four shape labels, but that does not answer questions about a specific wall transition, step, tanning ledge, surface texture, water depth, or obstruction. Those details need an exact-model answer from Maytronics, not a guess based on the family name.

The S100 is cable-powered. Its page lists no anti-tangling swivel, and the exact technical table does not publish a cable-length measurement. Keep the pool-size rating distinct from the lead length: a longer cable, if present in a particular offer, would not change the 33-foot pool limit. Check the exact carton and instructions for the cable and power-supply configuration.

A weekly timer without app control

Maytronics lists a two-hour default cycle and a weekly timer, but Mobile Application and Automation Mode are both No. The listing does not establish app setup, remote steering, or alternate cycle durations. That distinction is useful: someone who wants a scheduled routine may consider the S100, while someone who needs phone configuration or a connected-status feature should compare a separately numbered model that documents those functions. The timer entry alone should not be read as proof of a particular control interface or behavior.

The product page also lists an active brush and one standard brush, and describes CleverClean navigation. Those are manufacturer specifications and feature claims, not a measured result. They do not promise that a single cycle will reach every corner or climb every wall profile in every pool.

Two filter types are listed, but no micron grade

The exact U.S. page calls the main filter a “Combine Filter Kit,” says the basket is top-access, and lists an additional Ultra-Fine Filter Kit in the box. This is a meaningful distinction from a base configuration whose page shows no extra kit. The specification does not give a particle-size rating, so “ultra-fine” should remain the manufacturer’s kit label rather than a numeric filtration promise. The linked S100 manual portal identifies a user manual and quick guide; the English instructions file linked there has a “Robotic Pool Cleaner Mass 10” cover. That title is not the retail name, so confirm the applicable edition with support if a detail is unclear.

The instructions describe lifting out the basket, rinsing it after use, and periodically cleaning the filter panels. They recommend cleaning after each cycle and checking the panels at least monthly. Verify that the supplied basket and filters match the 99996121-USF package.

Setup and care deserve an exact manual check

The linked manual’s safety section calls for the originally supplied power supply, a GFCI- or ELI-protected outlet, keeping the supply out of standing water, and placing it at least 12 feet from the pool edge. It also says not to enter the pool while the cleaner is working and to unplug power before servicing. Follow the current instructions supplied for the actual unit and local electrical requirements. The guide also covers impeller cleaning and off-season storage; confirm its diagrams and power-supply edition against the cleaner received.

Maytronics lists a robot weight of 14.818 pounds and a two-year warranty. The exact S100 column’s caddy/stand field is blank, so this review does not treat a caddy as included. A seller may combine the same cleaner with accessories; that bundle needs its own contents check. The page’s listing date or an online offer also cannot establish current stock or the warranty applicable to a particular seller.

Where it sits beside nearby Dolphin options

The S100’s 33-foot floor-and-wall brief differs from the Explorer E10 assessment, whose exact listing is 30-foot and floor-only: Maytronics lists an additional Ultra-Fine kit and weekly timer for the S100, but not an app. The Nautilus CC is also listed for 33-foot floor-and-wall coverage, while its exact page does not list a weekly timer or extra Ultra-Fine kit. By contrast, the CC Pro is listed for up to 50 feet and floor, wall, and waterline work, with MyDolphin Plus; that broader feature set is a different assessment, not a reason to stretch the S100’s rating. Check each exact product number rather than treating those differences as interchangeable Dolphin family features.

Who should shortlist it—and what to verify

The S100 is worth comparing when the pool is within the stated 33-foot limit, floor and walls are required, a weekly timer is useful, and the extra Ultra-Fine kit matters. It is a weak fit when waterline cleaning, app support, a swivel cable, an included caddy, or a known cable length is essential. The page does not resolve those gaps by implication.

Before choosing a seller, match the carton to Product No. 99996121-USF, confirm the combination basket and additional Ultra-Fine kit, verify the supplied power unit and applicable manual, and ask how the two-year warranty applies to that exact offer. The official U.S. S100 page and the manual portal for that product number are the primary references used here. Neither the specification sheet nor this review is a hands-on performance test.