- Type
- Countertop, corded, plug-in
- Pressure range
- 10 settings on Waterpik's PRECISIONPULSE pump (PSI not published)
- Reservoir
- 22 oz (651 ml), Waterpik rates it at 90+ seconds of flossing time per fill
- Tips included
- 7: 4 Precision, 1 Orthodontic, 1 Pik Pocket, 1 Plaque Seeker
- Tip replacement
- Waterpik recommends every 3 to 6 months; a 4-pack of Precision tips runs about $10 to $13 at most retailers
- Battery
- None, corded, plugs into a wall outlet (120VAC/60Hz, North America only)
- Dimensions
- 10.35 x 4.70 x 3.80 in, 1.46 lb (Waterpik's listed unit dimensions)
- Warranty
- 3-year limited warranty (Waterpik)
Waterpik
Waterpik Aquarius WP-660
A countertop water flosser with a large reservoir and 10 pressure settings, built for daily use at one bathroom sink.
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All prices
| Store | Price | Checked | |
|---|---|---|---|
| Waterpik Best price | $99.99 | ✓ AUG 30 | Go to store |
Prices were checked on the dates shown and can change at any time. The store page is always authoritative. Shipping and taxes are not included.
First verified Aug 30, 2026. When a later check finds a different price, it gets logged here.
Our verdict
Where it wins
- Large 22 oz reservoir means fewer refills mid-session than the cordless models in this category
- 10 pressure settings give a wide range from gentle to strong
- Comes with 7 tips covering orthodontic and periodontal-pocket use, not just a single standard tip
- 3-year warranty is longer than Waterpik's own cordless line
Where it loses
- Corded and countertop-only, it needs a dedicated spot near an outlet and does not travel well
- Replacement tips are a recurring cost: Waterpik says to swap them every 3 to 6 months, and a 4-pack runs about $10 to $13
- 120VAC/60Hz only, not usable in countries on 220-240V without a voltage converter
The Aquarius WP-660 is Waterpik's mainstream countertop model, and the big reservoir plus 10-setting pressure dial make it the one to buy if the flosser is going to live permanently on one bathroom counter. It is not built for travel or small bathrooms, that job goes to Waterpik's own cordless line. Buy it if you want the largest tank and widest pressure range in Waterpik's countertop lineup and don't mind the cord and counter space; skip it if you need something portable or share a bathroom with limited counter room.
Also in water flossers
Aquasonic Precision Cordless Water Flosser
A budget cordless water flosser with 8 pressure levels and a small tank, sold at a fraction of the price of the name-brand cordless models.
Philips Sonicare Power Flosser 3000
A cordless, rechargeable water flosser with two cleaning modes and a compact 250 ml tank, sized for a bathroom counter or a bag.
Waterpik Cordless Advanced 2.0 WP-580
A battery-powered, waterproof water flosser sized for travel or a small bathroom, with a smaller tank than the countertop models.
More on the Waterpik Aquarius WP-660
Common questions
What pressure does the WP-660 flosser at?
It has 10 pressure settings on Waterpik's PRECISIONPULSE pump. Waterpik does not publish exact PSI figures for the setting range, but the dial goes from a gentle low setting up to a strong high setting suitable for daily use.
How often do the tips need replacing?
Waterpik recommends replacing tips every 3 to 6 months. A 4-pack of Precision tips typically costs about $10 to $13, so budget for that as an ongoing cost on top of the flosser itself.
Does it prevent gum disease?
No single device prevents gum disease. Waterpik says the WP-660 removes up to 99.9% of plaque bacteria from treated areas in its own lab testing and cites clinical studies showing it is more effective than string floss at reducing bleeding and plaque in study participants. Those are manufacturer-cited results, not a guarantee for any individual.
Can I use it outside North America?
Waterpik lists the WP-660 as compatible with 120VAC/60Hz outlets for use in North America only. For other voltages, Waterpik sells separate international models.
Prices last verified Aug 30, 2026.