Track RO performance before watering sensitive plants. Enter flows and salinity to reveal efficiency fast. Download reports, spot waste, and protect your garden year-round.
| Feed (L/h) | Permeate (L/h) | Concentrate (L/h) | Recovery (%) | Feed TDS (ppm) | Permeate TDS (ppm) | Rejection (%) |
|---|---|---|---|---|---|---|
| 600 | 240 | 360 | 40.00 | 900 | 30 | 96.67 |
| 500 | 250 | 250 | 50.00 | 650 | 25 | 96.15 |
| 420 | 168 | 252 | 40.00 | 1200 | 60 | 95.00 |
Recovery is the percentage of feed water converted into usable permeate. Higher recovery saves water, but it also concentrates salts in the reject stream, increasing scaling risk.
For delicate plants, consistent permeate quality is often more important than maximizing recovery. Track trends weekly and investigate sudden changes in rejection or flow balance.
Reverse osmosis recovery shows how efficiently a garden RO system converts feed water into usable permeate. If your feed flow is 600 L/h and permeate is 240 L/h, recovery is 40%, leaving 360 L/h as concentrate. Tracking this ratio helps you plan irrigation volume and manage waste.
Most small systems operate around 35–60% recovery. At 50% recovery, every 1 liter of permeate produces about 1 liter of concentrate, which is manageable for drain or reuse. For garden use, many owners target 40–55% to balance savings and membrane life. Pushing beyond 70% can increase scaling potential because salts concentrate faster in the membrane channels.
Flow balance is a practical troubleshooting check. In steady operation, Qf should be close to Qp + Qc. A deviation above 2% often points to inconsistent units, meter drift, air in the line, or a partially blocked restrictor. Daily permeate is simply Qp multiplied by runtime hours, such as 0.25 m3/h for 4 hours equals 1.0 m3/day. Check pressures too: low feed pressure reduces permeate, while high pressure can mask fouling until rejection drops.
TDS inputs add a quality lens. If feed TDS is 900 ppm and permeate is 30 ppm, rejection is 96.67%, which is typical for healthy membranes. Sudden rejection drops below 90% may indicate membrane damage, O-ring bypass, or sampling errors. For sensitive plants, stable permeate TDS matters more than chasing maximum recovery.
Use results to set maintenance benchmarks. Record recovery, rejection, and permeate per membrane each week. A gradual permeate decline with stable rejection suggests fouling and warrants prefilter checks or cleaning, while rejection decline suggests integrity issues. When concentrate is reused for rinsing paths or ornamentals, log that volume separately. Exporting CSV/PDF keeps a clear history for seasonal irrigation planning and filter replacement intervals.
Many small units run 35–60% recovery. A common target is 40–55% for stable permeate and lower scaling risk. If you exceed 70%, monitor concentrate buildup and follow the membrane maker’s limits.
Water viscosity changes with temperature. Warmer water usually increases permeate flow, raising recovery if feed flow stays constant. Colder water lowers permeate flow, so recovery drops unless pressure or restrictor settings are adjusted.
No. Enter any two of feed, permeate, and concentrate. The calculator solves the third using flow balance. Use one unit for all fields to avoid incorrect recovery results.
If rejection falls below about 90%, check for membrane damage, bypass around seals, exhausted carbon, or sampling error. Also verify the feed TDS reading; a faulty meter can distort the rejection percentage.
Sometimes. Concentrate contains higher salts than feed. It can be suitable for rinsing tools, paths, or salt-tolerant ornamentals, but avoid sensitive plants and seedlings. If unsure, measure TDS and water sparingly.
Weekly logging is enough for most home systems. Record feed, permeate, and TDS at the same operating condition. Increase to daily checks after filter changes, membrane cleaning, or when you notice taste or plant stress.
Ideally, Qf equals Qp plus Qc. A large deviation suggests wrong units, a faulty flow meter, leaks, air bubbles, or restrictor issues. Fixing balance improves confidence in recovery calculations and trend comparisons.
Important Note: All the Calculators listed in this site are for educational purpose only and we do not guarentee the accuracy of results. Please do consult with other sources as well.