The short answer
Do not select an RO system from TDS alone. For municipal water, a basic analysis may be enough. For well or brackish water, hardness, iron, manganese, turbidity and scaling risk can change the pretreatment route substantially.
If you already have a laboratory report, send the complete report rather than only the TDS value.
Why the water test matters before the quotation
An RO unit is not simply a pump and a membrane sized by litres per hour. The membrane only works reliably when the water reaching it has been prepared for the actual risks in the source water.
Two sources can show a similar TDS value and still require different systems. One may be relatively clean municipal water with chlorine present; another may be well water with hardness, iron and suspended solids. The output capacity may be the same, but the treatment route should not be.
Key point
The parameters worth checking first
You do not always need a long laboratory report before the first discussion. But the following parameters are the ones most likely to change a practical small RO configuration.
Watch out
A handheld TDS meter cannot tell you whether the water contains excessive hardness, iron, manganese, turbidity or microbiological contamination.
What to test depends on the water source
Municipal water
Start with TDS or conductivity, hardness, pH and available information about chlorine and turbidity. Municipal water is often more stable, so the first configuration can usually be simpler.
Well / borehole water
Hardness, iron, manganese and turbidity become much more important. Source conditions may also change seasonally, so a complete laboratory report is more valuable.
Brackish water
Salt concentration and scaling risk matter more. TDS, hardness, alkalinity and the overall ionic profile become increasingly useful for recovery and membrane decisions.
Seawater
Seawater desalination requires a different pressure, membrane and pretreatment approach. A proper water analysis and site review should be treated as part of the design process, not an optional extra.
If you have a laboratory report, send the full report
Do not crop the report down to one number. The relationship between parameters is often more useful than a single result. A full report also helps identify what is missing before a final configuration is issued.
Source
Municipal, well, brackish or seawater
Water data
Report, TDS and known risks
Use & demand
Application, L/hour and operating time
Configuration
Pretreatment, RO and finishing modules
What to send when asking for a quotation
For a useful first proposal, AquaOxy normally needs four pieces of information. If one item is unavailable, send what you know rather than guessing.
Technical note
Final pretreatment, recovery and membrane configuration should be based on the complete source-water condition and project requirements, not on a generic capacity chart alone.
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