Dolphin S400 Review

What features does it have?

The Dolphin S400 sits near the top of the S-series, combining capable wall climbing with convenient weekly programming for hands-off cleaning in 2026. Here's a clear-eyed look at its strengths and limits.

Wall Climbing

Clean like a pro. With wall coverage, the Dolphin S400 can clean and scale your walls with precision and power. While Wall Climbing is a great feature, don't get this confused with the superior waterline cleaning feature.

What is Dolphin S400 missing?

Waterline Cleaning

Dolphin S400 does not included waterline cleaning. Not only is this an essential feature that you'll want when looking for a pool robot, but one you will likely need. Waterline cleaning enables the robot to climb and reach the dirtest part of your swimming pool. Without this feature, you'll still need to manually clean your waterline by hand with a brush to prevent any algae or scum that builds up. It is one feature that you'll need that is not included with the Dolphin S400.

Leaf Bag

With leaves being a common issue, it would be safe to assume most pool robots utilize a leaf bag. Well, no so fast. Nearly every robotic pool cleaner is missing a leaf bag, except the Dolphin Premier. If you have a lot of leaves, this is the best pool robot for leaves. Not to mention the Premier's 3 year warranty, Dual Commercial Motors, and Multi-Media™ make it one of the best models available.

Bear in mind the S400 is built around standard filters rather than NanoFilters, and it isn't a ProLine or Max-Series model. If you're after the strongest motors and finest debris capture available, step up to a ProLine cleaner such as the Dolphin Premier, or compare the Max-Series.

What's included with the Dolphin S400?

The Dolphin S400 includes everything you'll need. Here is what is included with the unit:

• Dolphin S400 Unit
• 60 ft Cord with Anti-Tangle Swivel
• Programmable Weekly Timer
• Standard Filters
• 2 Year Warranty

How to set up the Dolphin S400

Simply plug and play. All robotic pool cleaners are ready to go right out of the box. No booster pump or assembly needed. The S400 has everything needed to get started in its box. It's that easy.

Comparing S-series models? Read our Dolphin S300 review and Dolphin S200 review, or step up to the flagship Dolphin Sigma review.

Why Poolbots?

No one knows robotic pool cleaners better than us. With over 25 years in the swimming pool industry and as a Dolphin Authorized Dealer, every robot we sell is backed by the full, non-prorated manufacturer's warranty — never a reduced or prorated version. Every order ships free, and is protected by our 30-Day Trial with NO restocking fee, ever, so you can put it to work in your own pool completely risk-free.

Ready to buy, or want a second opinion first? See how the best robots compare or contact our pool experts — we'll help you pick the perfect cleaner and ship it straight to your door.