Runner-up
This countertop water flosser cleans as well as our top pick, and it has the same warranty and 10 pressure settings. But it’s slightly larger, and it needs an outlet.
If you don’t mind plugging in a water flosser, the Waterpik Aquarius is a solid model, and it provides a similar experience to that of our top pick. And like the Ion Professional, the Aquarius left our mouths feeling totally clean, thanks to its strong, continuous water stream (which is similar to that of our top pick). With its 10 settings, the Aquarius provides plenty of options for finding the pressure, pulse, and stream size that feels good to you.
You don’t have to deal with a charging system or batteries. The Aquarius plugs into the wall via a roughly 4-foot electrical cord. (Unlike the Ion Professional, this model has to remain plugged in to operate.) While there are more reports of the Aquarius breaking down or becoming caked with mold than we’d like, in our many years of research and long-term testing, we’ve found the Aquarius to be a reliable device.
It’s easy enough to clean. Although the Aquarius is not quite as simple to clean as the Ion Professional, it does have a wide, dishwasher-safe reservoir, which holds 22 ounces of water (or diluted mouthwash) for at least a single flossing session.
It’s plenty powerful. The floss mode delivers a continuous stream of water, and we found that it effectively cleaned our teeth.
There’s also a gentler option. The massage mode is a pulsing stream, and it’s gentler than the standard stream. This mode also seemed to clean well, and it filled our mouths with water at a slower rate, which in turn led to less-awkward drooling.
You can choose from several tips and streams. Like the Ion Professional, the Aquarius has a one-minute timer that pauses after 30 seconds, to remind you to switch from your top or bottom teeth, as well as 10 pressure settings (the same number our top pick has). It comes with seven tips (of four different types).
It has onboard tip storage. Unlike the Ion Professional, this model has a spot (next to the tank) to store two of the seven tips it comes with. This is handy if you want to share the flosser with family members or switch between a couple of tip types yourself.
Like the Ion Professional, the Aquarius has a three-year warranty.
Flaws but not dealbreakers
It’s a bit big. In part due to the bulky power cord, this model generally takes up more counter space than our other picks.
The hose is a touch shorter than the hose on our top pick. The curly hose connecting the handle to the tank is about 33 inches long, so it’s about an inch shorter than the Ion Professional’s.
