Aquarium Water Change & Siphon Speed Calculator

Aquarium Water Change & Siphon Speed Calculator

Siphon & Water Change Calculator

Torricelli’s Law Interactive Simulator

Water to Drain 30 L
Hose Inner Diameter 12 mm
Height Drop (Surface to Bucket Outlet) 50 cm
Dynamic Visualizer
Estimated Time
0m 0s
Total drainage time
Initial Flow Speed
0.00 L/s
Peak discharge rate

* Calculated using Torricelli’s Law ($v = \sqrt{2gh}$) with standard fluid friction compensation ($\sim C_d = 0.62$). Real-world speed may vary based on hose bends and debris filters.

Key Features

  • Torricelli’s Law Engine: Calculates dynamic flow velocity and total drainage duration using Torricelli’s theorem ($v = \sqrt{2gh}$), incorporated with standard fluid friction coefficient parameters.
  • Dual Unit System Support: Toggle seamlessly between Metric (Liters, Millimeters, Centimeters) and Imperial (Gallons, Inches) units without losing your relative input values.
  • Interactive Visualizer: Features a real-time animated graphic illustrating liquid level drops and active water stream discharge intensity as parameter sliders move.

How to Use

  1. Select Unit System: Choose between Metric or Imperial depending on your preferred measurement units.
  2. Adjust Water Volume: Slide the Water to Drain bar to set the total volume of water you plan to drain during the water change.
  3. Set Hose Diameter: Adjust the Hose Inner Diameter slider to match the precise internal measurement of your siphon tube.
  4. Define Drop Height: Set the Height Drop slider to represent the vertical distance between the aquarium water surface and the drainage bucket outlet.
  5. Review Live Results: Instantly read your calculated Estimated Time and Initial Flow Speed on the dynamic dashboard cards below.

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