Salt Cell Output Calculator

Calculator

Cell rated output

Use the rating from the manufacturer label.

Output setting

Controller percentage or duty cycle setpoint.

Runtime

hours/day

Total hours the cell is energized daily.

Water volume

Reservoir, pond, or tank volume for ppm estimate.

Water temperature

°C

Apply temperature factor

Salinity

ppm

Apply salinity factor

Low salt can reduce output. Use your sensor reading.

System efficiency

Accounts for wiring, flow, controller behavior, and losses.

Cell condition

Scale buildup and age can reduce production capacity.

Chlorine demand

ppm/day

Optional daily loss from sunlight, organics, and biofilm.

Target ppm increase

ppm

Optional helper to estimate percent or runtime needed.

Tip: Use measured free chlorine and adjust inputs until the estimate matches reality.

Example Data Table

Rated (g/h)	Setting (%)	Runtime (h)	Volume (L)	Factors	Produced (g)	Rise (ppm)
20	60	10	2000	Eff 95%, Cond 90%	102.6	51.3
10	40	8	5000	Eff 90%, Cond 80%	23.0	4.6
30	70	12	1500	Eff 100%, Cond 95%	239.4	159.6
18	50	6	3000	Eff 92%, Cond 85%	42.2	14.1
25	80	4	10000	Eff 88%, Cond 90%	63.4	6.3

Example values are illustrative. Actual output varies by equipment and water chemistry.

Formula Used

1) Convert the rated output

If rating is in lb/day, convert to grams/hour.

rated_gph = (lb_per_day × 453.59237) ÷ 24

2) Apply control and real-world factors

Combine percent setting with efficiency, cell condition, and optional temperature/salinity.

effective_gph = rated_gph × (percent/100) × efficiency × condition × temp_factor × sal_factor

3) Convert grams produced to ppm rise

1 ppm ≈ 1 mg/L. Convert grams to milligrams, then divide by liters.

grams = effective_gph × runtime_hours

ppm_rise = (grams × 1000) ÷ volume_L

net_ppm = max(ppm_rise − demand_ppm, 0)

How to Use

Enter the cell’s rated output from its label or manual.
Set your controller percentage and daily runtime hours.
Add your reservoir or pond volume for ppm estimation.
Optionally apply temperature and salinity factors using measurements.
Use efficiency and cell condition to match real performance.
Press Calculate to see production, ppm rise, and exports.
Measure free chlorine, then tune inputs to your system.

Output rate and runtime

Salt cell production is usually stated as grams per hour or pounds per day. The calculator converts the rating, then scales it by controller percentage and runtime hours. For greenhouse tanks, longer runtime at a lower percentage often stabilizes residual chlorine better than short, high bursts. Use the effective output rate to compare seasonal schedules. Record actual free chlorine weekly to validate the predicted rise trend.

Water volume and ppm rise

Grams produced become an estimated concentration increase using ppm ≈ mg/L. When volume is large, the same production yields a smaller ppm rise, so dosing feels slower. Smaller nurse tanks respond quickly and may overshoot targets. Always enter the best available volume estimate, including headspace limits and usable drawdown. If unsure, measure fill time with a meter and stopwatch once.

Efficiency and cell condition

Real systems rarely match nameplate output. Flow limits, controller behavior, voltage drop, and scaling reduce performance. The efficiency input lets you capture these site effects, while the cell condition factor represents age or fouling. If test-strip readings are consistently below expectation, reduce condition or efficiency until the estimate aligns. Cleaning the cell and stabilizing flow often restore output within days.

Temperature and salinity factors

Cold water can lower electrolysis output and may trigger protective modes on some controllers. Low salinity can also reduce current and production. The optional factors provide a practical adjustment when you have measured temperature and salinity. Keep them conservative, and rely on field testing to confirm safe, plant-compatible residuals. When factors are off, disable them and adjust efficiency instead manually.

Planning daily demand and targets

Chlorine demand represents daily loss from organics, sunlight exposure, and biofilm. Entering demand helps you forecast net ppm gain rather than gross production. The target helper estimates either the percentage needed for a fixed runtime or the runtime needed for a fixed percentage. Use it to plan consistent sanitation without overcorrecting. Document settings changes so operators can repeat successful dosing protocols later.

FAQs

1) What rating should I enter if my cell is listed in lb/day?

Enter the manufacturer number and choose lb/day. The calculator converts it to grams per hour automatically, so runtime and percentage adjustments remain consistent across different brands and label styles.

2) How do I estimate tank volume if the shape is irregular?

Use any reliable method: flow-meter fill totals, a known pump rate with timed fill, or dimensional estimates. Better volume inputs improve ppm results and reduce the risk of over- or under-dosing.

3) What does “chlorine demand” represent here?

It is the daily ppm loss from sunlight, organics, and biofilm. Adding demand helps estimate net ppm gain, which is more useful for planning stable sanitation than gross production alone.

4) Should I always enable temperature and salinity factors?

Only if you have measured values and you want an extra adjustment. If you are unsure, keep them off and tune efficiency and cell condition using real test results from your system.

5) Why can the ppm rise look very large in small tanks?

Because ppm is concentration. A fixed mass of chlorine in fewer liters yields a higher ppm increase. Always verify with a test kit, and consider lowering percentage or shortening runtime for small volumes.

6) What is the best way to use the CSV and PDF exports?

Export after each adjustment and store the files with date, crop zone, and tank ID. Over time, the records help you spot performance drift, scaling effects, and seasonal runtime changes.