Standard RO selection guide
How to choose a 250, 500 or 1000 L/h RO system
Match production capacity to daily demand, peak use and available operating hours. Then check feedwater quality, storage and the conditions at your site.
A model’s nominal flow is a starting point for planning. It does not establish the water quality, daily output or installation scope your project will achieve.
Compare your water demand · Work through a demand example · Check equipment scope · Send your requirements
Compare capacity using your water demand
Enter your daily use and available RO operating time. Add a short peak only if the RO system can operate throughout that peak.
This is an arithmetic comparison using nominal output, not a final equipment recommendation. Actual output varies with feedwater, temperature and operating conditions. Peak calculations assume nominal RO production throughout the peak; the result is a water-volume gap, not a tank size or complete supply design.
Calculation inputs stay in this page. No enquiry is submitted by calculating or copying. Paste the brief into your enquiry and add your country, water source, application, required water quality and site conditions.
Prepare an enquiry brief with your team
Record your water demand, feedwater information, site conditions and supply responsibilities in the four-sheet English workbook. Keep unknown details as “To be confirmed”.
Download the RO project brief (Excel)
XLSX · 4 worksheets · 31 KB. Complete the blue cells and send the file by email alongside your supporting water report or site photos.
Start with daily demand and operating hours
Divide the required daily volume by the hours available for water production. Check the result against actual operating conditions, including water temperature, feedwater, flushing, maintenance and downtime.
Example: 3,000 litres per day, eight production hours
The initial calculation is 3,000 ÷ 8 = 375 L/h. At nominal flow, the three models would produce:
- QZ-RO250: 250 × 8 = 2,000 litres.
- QZ-RO500: 500 × 8 = 4,000 litres.
- QZ-RO1000: 1000 × 8 = 8,000 litres.
Under these assumptions, start by assessing RO500. Check the operating margin and water conditions before selecting it. These are planning calculations, not guaranteed daily yields.
If only four hours are available, RO500 produces just 2,000 litres at nominal flow. Reassess capacity or the operating schedule; a larger tank alone cannot make up a daily production shortfall.
Check peaks and usable storage separately
A production line may draw water faster than the RO unit produces it. Storage can bridge a short peak if enough usable water is available beforehand and the distribution pump provides the required flow and pressure.
For a 1,000 L/h demand lasting one hour, with the RO unit actually producing 500 L/h during that period, the shortfall is 500 litres. Review at least this usable reserve, the initial water level and the time available to refill. Usable storage is different from the tank’s nominal volume.
Also check how stored water will be kept suitable for its intended use. Do not select a tank from volume alone.
Planning around a 500 L/h system?
Compare available production hours with daily volume, peak use and the time needed to refill storage.
Compare capacity and equipment scope
QZ-RO250 · 250 L/h
Pretreatment and RO unit. Raw-water pump, water tanks and distribution pump are not included.
Designed for a mains-water connection, subject to inlet-condition review.
QZ-RO500 · 500 L/h
Pretreatment and RO unit. Raw-water pump, water tanks and distribution pump are not included.
Designed for a mains-water connection, subject to inlet-condition review.
QZ-RO1000 · 1000 L/h
Raw-water pump, pretreatment and RO unit. Water tanks and distribution pump are not included.
Confirm the electrical configuration and installation conditions for your site.
Confirm the final equipment list, interconnecting pipework, drainage, installation and commissioning responsibilities in the proposal.
Flow alone cannot determine suitability
- Feedwater: identify the source and provide the original water-analysis report. Groundwater may need a different pretreatment arrangement.
- Water quality at the point of use: state the production process and its required specification. Do not rely on TDS alone.
- Site conditions: confirm incoming-water pressure, electricity, drainage and maintenance access.
- Production continuity: explain whether storage, standby equipment or a different operating schedule is needed.
Complex feedwater, tighter quality requirements, demand above 1000 L/h or additional standby requirements should move into a project-specific review.
Send a short production-water brief
Include your country, application, daily volume, peak flow and duration, available production hours, storage conditions, source water and required water quality. Add the original analysis report if available.