For busy homes and small businesses
More water, the same clean taste
If a smaller purifier struggles to keep up with your household or your shop, the 400 GPD is the next step up. It gives you twice the daily capacity of our 200 GPD model, so there is enough clean water even when several people are filling glasses and bottles through the day.
It runs on tap, well or municipal water. If you are on a well, we suggest getting the water tested first, because well water can carry things that an RO system alone is not meant to handle. Final water quality depends on your incoming water, the condition of the membrane and regular servicing.
Why people pick the 400 GPD
- Twice the daily capacity of the 200 GPD model
- High-pressure pump for a steady flow
- 11 gallon pressurized storage tank
- Works with tap, well or municipal water
- Fits under the sink or on the wall
How it works
What happens to your water, step by step
Three prefilters clean the water first and protect the membrane. The membrane does the heavy lifting, and one last filter takes care of the taste.
Sediment Filter, 20"
Catches sand, rust, dust and other visible particles so they do not clog the filters that come after it.
Carbon Block Filter, 20"
Helps cut down chlorine, smells and organic chemicals, and shields the membrane from damage.
GAC Filter, 20"
Granular activated carbon takes the taste and odour a step further and helps reduce unwanted chemicals.
High-Performance RO Membrane
The heart of the system. It is built to help reduce dissolved salts, heavy metals and other contaminants.
Inline Post Carbon Filter
A last carbon pass right before the tap, so the water tastes fresh when it reaches your glass.
Pump, tank and installation
Built to keep up with demand
A high-pressure booster pump gives the membrane the pressure it needs for a good flow rate. The 11 gallon food-grade pressurized tank stores purified water, so it comes out quickly when you open the tap.
The system works at 30 to 100 PSI. You can fit it under the sink or mount it on a wall, depending on how much space you have.
Ask about thisSpecifications
| Filtration capacity | 400 GPD |
|---|---|
| Filtration stages | 5-stage RO |
| Membrane type | High-performance RO membrane |
| Prefilters | 20" sediment, carbon block, GAC |
| Post filter | Inline carbon filter |
| Pump | High-pressure booster pump |
| TDS reduction | Helps reduce TDS, heavy metals and chemicals |
| Storage tank | 11 gallon, food-grade, pressurized |
| Operating pressure | 30-100 PSI |
| Inlet water source | Tap, well or municipal water |
| Installation | Under-sink or wall-mounted |
Exact configuration may vary by model and installation needs.
Key features
What you get
Room to grow
400 gallons a day is plenty for a large family, a busy office or a café.
Steady flow
The high-pressure pump keeps the flow rate up when the system is working hard.
Cleaner, better-tasting water
Carbon block, GAC and post carbon filters work together to improve how your water tastes and smells.
Ready when you are
The 11 gallon pressurized tank keeps purified water on standby.
Works with your supply
Suitable for tap, well or municipal water, with a water test recommended for wells.
Flexible setup
Goes under the sink or on a wall, whichever suits your kitchen or back-of-house space.
Why Aqua Best
We help you pick the right size
We supply, install and service water purification systems for homes, businesses and industry across Dubai and the UAE. Tell us how much water you use in a day and what your supply looks like, and we will tell you honestly whether the 400 GPD is the right fit or whether a smaller or bigger system makes more sense.
Servicing and filter changes
How often you need to change filters depends on your water and how much of it you use. As a rough guide, prefilters are changed every 3 to 6 months, and the RO membrane lasts longer than that. We will work out a schedule that suits you.
Our support includes
- Help choosing the right system
- Installation
- Filter replacement
- RO membrane replacement
- Booster pump servicing
- Regular maintenance
- Replacement parts
- Annual Maintenance Contracts (AMC)
Where it is used
- Homes
- Offices
- Cafés
- Small businesses
Need a high-capacity RO purifier?
Message us with your daily water use and we will recommend the right system and a price.
400 GPD purifier questions
What does 400 GPD mean?
GPD means gallons per day. It is the amount of purified water the membrane can make in 24 hours under good conditions. Real output depends on your water temperature, pressure and how much dissolved salt is in the incoming water.
How is it different from the 200 GPD model?
It has the same five-stage layout, but twice the daily capacity, a high-performance membrane and a high-pressure booster pump. It is meant for places that use more drinking water.
Can I use it with well water?
It is suitable for tap, well or municipal water. For well water, we recommend a water test first so we can check if extra pre-treatment is needed.
Is it good enough for a café or office?
For most small cafés and offices, yes. If your demand is much higher, we can suggest a larger commercial RO system instead.
Where can it be installed?
Under the sink or on a wall. Send us a photo of the space or tell us the layout, and we will suggest the best spot.
How often should I change the filters?
Prefilters are usually changed every 3 to 6 months, and the RO membrane lasts longer. Heavy use or hard water can shorten that, so we will set a schedule based on your situation.
Do you install it in Dubai?
Yes. We install and service water purifiers in Dubai and across the UAE.
Can I get a quote?
Yes. Tell us your property type and how much water you use, and we will send you a quote.

