Track RO product and waste water for garden tasks. View ratio, recovery, and monthly cost. Use these results to tune pressure and garden reuse.
| Scenario | Product (L) | Waste (L) | Waste per 1 Product | Recovery (%) | Practical note |
|---|---|---|---|---|---|
| Efficient setup | 12 | 12 | 1.00 | 50.0 | Good pressure and clean prefilters. |
| Typical home RO | 10 | 30 | 3.00 | 25.0 | Common baseline for many membranes. |
| High waste | 8 | 40 | 5.00 | 16.7 | Check restrictor, pressure, or membrane age. |
| Low runtime session | 4 | 10 | 2.50 | 28.6 | Short runs can look worse if flushing occurs. |
| Optimized irrigation reuse | 15 | 20 | 1.33 | 42.9 | Reuse reject water for non-sensitive plants. |
Tip: If your readings vary, calculate a few runs and average them.
All calculations are performed internally in liters, then displayed in your chosen unit.
Reverse osmosis (RO) gives consistent water for seedlings and sensitive crops, but every liter of product water also produces reject water. Tracking the waste‑to‑product ratio helps you plan storage, reuse, and irrigation timing. For example, a 1:3 ratio means 10 L of product creates 30 L of reject, so your total feed demand is 40 L per run.
Recovery is the share of feed water that becomes product: Product ÷ (Product + Waste). A 25% recovery (typical 1:3) turns 40 L feed into 10 L product. If you run twice daily, that becomes 80 L feed/day and 2,400 L feed/month (30 days), which is useful when sizing barrels, drip schedules, and pump run time.
Many household membranes operate around 1:2.5 to 1:4 depending on pressure, temperature, and restrictor sizing. Low pressure can push ratios above 1:5, while a booster pump can improve recovery. Short sessions may look “worse” because initial flushing sends extra water to drain before steady production begins.
If your water price is per unit, the true cost is based on feed water, not product. At 1:3, every 1 unit of product requires 4 units of feed. So a 500 L/month garden RO output implies roughly 2,000 L/month feed. This calculator converts that into an estimated monthly cost and highlights how changes in ratio shift total usage. Even a move from 1:4 to 1:3 cuts feed demand by 20%.
Start with clean sediment and carbon prefilters, then verify pressure at the membrane. Replace a clogged flow restrictor or aging membrane if performance drops. For reuse, route reject water to lawns, ornamentals, wash-down, or pre‑watering beds. Avoid salt‑sensitive plants if the feed is mineral heavy, and periodically monitor soil salinity. Record readings monthly to spot slow declines early over time.
Many setups fall between 1:2.5 and 1:4. Lower is better if water quality stays stable. Use your baseline readings to judge improvements after maintenance or pressure changes.
Feed pressure, water temperature, and filter condition change output and waste. Short runs can also inflate waste because the system flushes before reaching steady flow.
Not always. Pushing recovery too high can increase scaling and shorten membrane life. Balance efficiency with stable production and follow your membrane’s recommended operating range.
Collect product in a marked container and time the run. For waste, divert the drain line into a bucket for the same duration. Repeat three runs and average results.
Often yes, but it depends on your source water minerals. Use it on tolerant crops or soil where salts won’t accumulate. Avoid seedlings and salt‑sensitive varieties if TDS is high.
Replacing clogged prefilters, correcting restrictor size, and ensuring proper pressure are common wins. If performance remains poor, a worn membrane may be the cause.
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.