Quick Presets
Optional
Loads target humidity, temps, airflow, and typical mist durations.
Inputs
Set to 0 if using fan CFM only.
1 CFM ≈ 1.699 m³/h.
Presets fill typical durations. Blank uses recommended duration.
Drainage & Overflow
Approximate the max continuous flow to your drain.
Catch cup or sump capacity before overflow to floor.
Scheduling
%
Skip decision checked at event start time.
Else the simulator’s RH is used for skip checks.
Weekday schedule
| Day | AM start | AM end | AM events | AM duration (min) | PM start | PM end | PM events | PM duration (min) |
|---|---|---|---|---|---|---|---|---|
| Mon | ||||||||
| Tue | ||||||||
| Wed | ||||||||
| Thu | ||||||||
| Fri | ||||||||
| Sat | ||||||||
| Sun |
CSV with headers e.g. time,rh or datetime,rh. Time can be HH:MM or full timestamp. RH in percent.
Example Data Table
| Preset | Volume (L) | Target RH (%) | Temp (°C) | ACH | Fan (CFM) | Nozzle (ml/min) | Events/day | Duration (min) |
|---|---|---|---|---|---|---|---|---|
| Dart Frog | 182 | 90 | 24 | 0.5 | 3 | 120 | 6 | 2.0 |
| Crested Gecko | 120 | 75 | 24 | 2 | 8 | 90 | 3 | 2.0 |
| Veiled Chameleon | 240 | 60 | 27 | 6 | 25 | 150 | 4 | 3.0 |
| Bearded Dragon | 250 | 40 | 35 | 8 | 35 | 0 | 0 | 0 |
| Tropical Plants | 45 | 85 | 23 | 0.2 | 0 | 60 | 2 | 1.5 |
Formulas Used
- Volume: V = (L × W × H) / 1,000,000 [m³]. Also in liters = V × 1000.
- Saturation vapor pressure (Magnus): Pws = 6.112 × exp(17.62 × T / (243.12 + T)) [hPa].
- Vapor pressure: e = RH/100 × Pws [hPa].
- Absolute humidity: AH = 216.7 × e / (T + 273.15) [g/m³].
- Airflow: Q = ACH × V + CFM × 1.699 [m³/h].
- Moisture loss (vent): Loss/hour = Q × max(0, AHinside − AHambient) [g/h].
- Daily loss: Loss/day = 24 × Loss/hour − substrate_evaporation [g/day], floored at 0.
- Initial raise: ΔMinit = V × (AHtarget − AHcurrent) [g].
- Misting addition: per event = total_nozzle_flow × duration × efficiency [g].
- Recommended duration (per event): duration = Loss/day ÷ (events/day × total_nozzle_flow × efficiency) [min].
- Drain liquid load: load = total_nozzle_flow × (1 − efficiency) [ml/min].
- Overflow rate while misting: max(0, load − drain_capacity) [ml/min]; event overflow = rate × duration [ml].
- Dynamic model: dAH/dt = −(Q/V)(AH − AHamb) + (mist + evap)/V [per min].
These relations approximate well-mixed air and practical drainage behavior during mist events.
How to Use This Calculator
- Choose a preset to auto-fill targets and a typical mist duration.
- Enter enclosure size, temperatures and ambient humidity. Verify with instruments.
- Set nozzle count, drain line and reservoir capacity for overflow checks.
- Select scheduling mode. Optionally sync times to lights and enable skipping.
- Import a sensor CSV if you want skip rules to follow real humidity.
- Click Compute to size durations, simulate swings, and view water plus overflow forecasts.
FAQs
They are engineering estimates based on well-mixed air and typical evaporation efficiencies. Real setups vary with enclosure leaks, microclimates, foliage, and warm surfaces. Tune with measurements over several days.
Ventilation alone may raise humidity. Increase airflow carefully, use desiccant media, or maintain drier rooms. Misting is typically unnecessary if ambient exceeds your target.
Start between 0.5 and 0.8 for fine mist nozzles with warm airflow. Heavier droplets or cold surfaces lower efficiency. Increase if you observe rapid absorption without pooling.
ACH scales with enclosure volume and is great for targets. CFM is useful when selecting a fan. You can set either or both; the calculator combines them.
Watch the dew point and keep it below the coolest glass temperature. Maintain airflow across surfaces, avoid stagnant corners, and cycle misting to allow partial drying.
Yes. Use their equivalent water delivery rates in ml/min. Efficiency can differ; foggers may reach higher efficiencies but can chill air. Adjust inputs and retest.