Yes, the Waterpik Aquarius is worth it, if you’ll use the timer. I use my Aquarius WP-660 every day along with string floss. My teeth feel cleaner, it clears out food that brushing misses, and my dentist noticed an improvement. My one real complaint is that it’s loud.
The short answer: the Aquarius ($99.99) and the Waterpik Ultra ($69.99) have the same pump: 10 pressure settings, 1,400 pulses a minute, a 22 oz reservoir and a 3-year warranty. The extra $30 buys a 1-minute timer with a 30-second pacer, a massage mode, an LED indicator, two more tips and a smaller footprint. If you don’t care about the timer, the Ultra is the better value. If noise matters, skip both and look at the Waterpik Promax.
Best countertop water flosser with a timer
Waterpik Aquarius WP-660
10 pressure settings, a 22 oz reservoir, a 1-minute timer, massage mode and 7 tips. It works well, but it's loud.
Best value countertop water flosser
Waterpik Ultra WF-100
The same 10-setting pump and 22 oz reservoir as the Aquarius for $30 less. No timer, no massage mode, 5 tips.
Waterpik Aquarius vs. Ultra at a Glance
These numbers come from Waterpik’s own spec sheets for the WP-660 and WF-100.
Waterpik Aquarius vs. Ultra
| Spec | Aquarius (WP-660) | Ultra (WF-100) |
|---|---|---|
| List price | $99.99 | $69.99 |
| Pressure settings | 10 | 10 |
| Pulses per minute | 1,400 | 1,400 |
| Flow rate | 13 oz per minute | 13 oz per minute |
| Modes | Floss and Hydro-Pulse Massage | Floss only |
| Timer | 1 minute with 30-second pacer | None |
| LED function indicator | Yes | No |
| Tips included | 7 | 5 |
| Reservoir | 22 oz, 90+ seconds | 22 oz, 90+ seconds |
| Base (width x depth) | 4.7 x 3.8 in | 5.6 x 5.3 in |
| Height with tip | 10.35 in | 9.9 in |
| Voltage | 120V, North America only | 100-240V, global |
| Warranty | 3-year limited | 3-year limited |
What’s the Same
The core of both machines is identical on paper. Both have 10 pressure settings, the same 13 oz per minute flow, the same 1,400 pulses per minute, a 22 oz covered reservoir rated for 90+ seconds, a 360-degree rotating tip, an on/off slider on the handle, a 52-inch cord and a 36-month warranty. They take the same tips. Both are rated 4.6 out of 5 on waterpik.com, the Ultra across more than 7,000 reviews.
So the cleaning itself shouldn’t differ. The water hits your gums at the same pressure range and pulse rate. What you’re paying for with the Aquarius is everything around the pump.
What the Extra $30 Buys
A timer and pacer
The Aquarius has a 1-minute timer with a 30-second pacer, which signals every 30 seconds so you can pace yourself around your mouth. The Ultra has no timer, so you judge the time yourself. This is the biggest practical difference.
Hydro-Pulse massage mode
The Aquarius has a second mode, Hydro-Pulse Massage, alongside the standard floss mode. I use the normal floss mode at a medium setting between 4 and 7. No systematic review I could find tests a massage mode separately, so treat it as a comfort feature, not a proven health benefit.
More tips, but a different set
The Aquarius comes with 7 tips: 4 Precision tips, plus one each of Orthodontic, Pik Pocket and Plaque Seeker. The Ultra comes with 5: one Precision tip, one Orthodontic, one Pik Pocket, one Plaque Seeker and an Implant Denture tip that the Aquarius doesn’t include.
Four Precision tips matter if a household shares one machine, because everyone gets their own standard tip. If you have implants, crowns or bridges, the Ultra’s box includes the tip for that, though Waterpik sells the same DT-100E tip separately for the Aquarius.
A smaller footprint
The Aquarius base is 4.7 x 3.8 inches. The Ultra’s is 5.6 x 5.3 inches, about two-thirds more counter area. The Aquarius stands a little taller at 10.35 inches with the tip.
What the Ultra does better
The Ultra is rated for 100-240V global voltage. The Aquarius is 120V North America only, so the Ultra is the one to buy if you’ll take it abroad or move.
How Loud Is It?
The Aquarius is louder than I expected. It’s a motor and pump on your counter, and it makes itself known when other people are asleep. It’s the reason I’d look at a quieter model if I were buying today.
Waterpik doesn’t list a noise rating for the Aquarius or the Ultra, and neither has its QuietPulse technology. In Waterpik’s own lineup, the Promax WF-23 is the countertop model with QuietPulse. It lists at $149.99, though Amazon has sold it for about $120, and it adds a SmartAdvance mode and a magnetic handle with a smaller 20 oz reservoir and 5 tips.
Aquarius vs. Cordless: Which Is Better?
Waterpik’s best-known cordless model, the Cordless Advanced 2.0 (WP-580), lists at $99.99, the same as the Aquarius. It’s a very different tool.
Waterpik Aquarius vs. Cordless Advanced 2.0
| Spec | Aquarius (WP-660) | Cordless Advanced 2.0 (WP-580) |
|---|---|---|
| List price | $99.99 | $99.99 |
| Pressure settings | 10 | 3 |
| Reservoir | 22 oz, 90+ seconds | 7 oz, up to 45 seconds |
| Modes | Floss and massage | Floss only |
| Timer | 1 minute with 30-second pacer | None listed |
| Tips included | 7 | 4 |
| Power | Corded, 120V | Rechargeable, up to 4 weeks per charge |
| Shower use | No | Yes, waterproof |
| Warranty | 3-year limited | 2-year limited |
The cordless model wins on space and travel. It runs on a built-in battery, charges by USB, and can go in the shower. But its 7 oz tank lasts up to 45 seconds, less than the Aquarius’s 1-minute timer, so you may refill it partway through, and you get 3 pressure settings instead of 10. Its warranty is a year shorter.
For daily use at home, the Aquarius is the better flosser for the same money. Buy the cordless if you have no free outlet or counter space, or if you travel often.
Best for travel and small bathrooms
Waterpik Cordless Advanced 2.0
A rechargeable, waterproof flosser with 3 settings and a 7 oz tank that lasts up to 45 seconds. Shower-safe.
Do Water Flossers Actually Work?
Waterpik says the Aquarius is “up to 2X as effective” as string floss for plaque and gum health. Independent reviews of the trials are more modest, and the evidence quality is mostly low:
- The 2019 Cochrane review of 35 randomized trials and 3,929 adults found that adding an oral irrigator to brushing may reduce gingivitis at one month (SMD -0.48, 4 trials, 380 people), but not at three or six months. It found no difference in bleeding sites or plaque versus brushing alone. Compared with floss, irrigators may reduce gingivitis at one month, with no difference for plaque. The certainty was low to very low, and the authors said the effect sizes may not be clinically important.
- A 2023 meta-analysis of 16 trials and 1,258 people with gingivitis found water-based cleaners plus brushing lowered bleeding between teeth compared with brushing alone and gave results comparable to brushing and flossing. Most trials that asked about preference found people favored the powered tools.
- A 2025 meta-analysis of 18 randomized trials found that for people without braces, water jets added no plaque benefit over floss and a slight improvement in gum bleeding.
- For braces, a 2024 meta-analysis found better plaque (MD -0.75) and bleeding scores (MD -0.17) when a water jet was added to brushing. Only four trials were pooled, and two of the six included trials had a high risk of bias.
The fair summary: a water flosser works about as well as floss for most people, with a small edge for bleeding gums, and a clearer benefit if you wear braces. It doesn’t support the “2X” claim, and the “99.9% of plaque bacteria” claim on the box comes from a lab study, by Waterpik’s own footnote. None of this research separates the Aquarius from the Ultra, since they share the same pump.
The best argument for one is that you’re more likely to keep doing it. I use mine daily on top of string floss. That’s my choice, not something the research says is necessary.
Which Waterpik Should You Buy?
Buy the Aquarius if you want the timer and pacer, a household will share it (4 Precision tips), or your counter is tight. It’s what I use, and it does the job well at about $100.
Buy the Ultra if you want the same cleaning for $30 less, you’ll watch the clock yourself, you need global voltage, or you have implants and want the Implant Denture tip in the box.
Buy the Promax if you floss while others are sleeping. Noise is my main complaint about the Aquarius, and the Promax is Waterpik’s countertop model with QuietPulse.
Buy the Cordless Advanced 2.0 if you travel, have no free outlet, or want to floss in the shower, and you can live with 3 settings and a 45-second tank.
Pair any of them with a good brush. Our best electric toothbrush guide covers the Oral-B and Sonicare models worth buying.
Waterpik Aquarius vs. Ultra FAQ
Is the Waterpik Aquarius worth it?
Yes, if you’ll use the timer and pacer. It cleans well, and I use mine daily. If you don’t need the timer, the Ultra has the same pump for $30 less, and if noise matters, the Promax is quieter by design.
What’s the difference between the Waterpik Aquarius and the Ultra?
The Aquarius adds a 1-minute timer with a 30-second pacer, a massage mode, an LED indicator, 7 tips instead of 5, and a smaller base. The pressure, flow, pulse rate, reservoir and 3-year warranty are the same. The Ultra costs $69.99 and works on global voltage.
Is the Aquarius stronger than the Ultra?
No. Both have 10 pressure settings, 13 oz per minute of flow and 1,400 pulses per minute.
What’s the difference between the Ultra and the Ultra Plus?
Waterpik’s spec pages list the same core numbers for both: 10 settings, a 22 oz reservoir, 5 tips, no timer and a 3-year warranty. The Ultra Plus (WF-150) lists for $79.99, $10 more than the Ultra.
What is the Aquarius Professional?
The WP-670 is an Aquarius sold through dental offices at $109.99. It has the same specs and swaps one Precision tip for a toothbrush tip and a tip storage case.
Is the Waterpik Aquarius loud?
Yes. It’s my biggest complaint. Neither the Aquarius nor the Ultra has QuietPulse, which Waterpik reserves for the Promax among its countertop models.
Is a cordless Waterpik as good as the Aquarius?
Not for home use. The Cordless Advanced 2.0 costs the same but has 3 pressure settings and a 7 oz tank that lasts up to 45 seconds, against 10 settings and 90+ seconds for the Aquarius. It’s better for travel and shower use.
Does a Waterpik replace flossing?
Systematic reviews find a water flosser works about as well as floss for plaque and slightly better for gum bleeding, though the evidence is low quality. I still use both. Ask your dentist what suits your teeth.
