Aquarium Filter Flow Rate Calculator
Fill in the values and the answer updates as you type.
How the Aquarium Filter Flow Rate Calculator works
Required flow = water volume × turnovers per hour. Many freshwater community tanks aim for about 4 to 6 turnovers an hour, planted and reef tanks often run more, and fish from still water such as bettas prefer less. Real flow is lower than the number on the box because filter media, tubing, and lift height add resistance, so rated flow = required flow ÷ (1 − loss). Example: A 200 liter tank at 6 turnovers an hour needs 1,200 liters an hour, so buy a unit rated near 1,714 liters an hour.
Inputs and results
The Aquarium Filter Flow Rate Calculator takes 3 inputs and gives 3 results.
What you enter
- Water volume (liters) — starts at 200.
- Turnovers per hour (x per hour) — starts at 6.
- Flow lost to media and tubing (%) — starts at 30.
What you get
- Required flow (liters/hour)
- Required flow (US gallons/hour)
- Rated flow to buy (liters/hour)
Example: Aquarium Filter Flow Rate Calculator with the starting values
With water volume 200 liters, turnovers per hour 6 x per hour and flow lost to media and tubing 30 %, the calculator returns:
| Required flow (liters/hour) | 1,200 |
|---|---|
| Required flow (US gallons/hour) | 317 |
| Rated flow to buy (liters/hour) | 1,714 |
Change any value above and the results update straight away.
Aquarium Filter Flow Rate Calculator FAQ
How do I use the Aquarium Filter Flow Rate Calculator?
Enter water volume, turnovers per hour and flow lost to media and tubing in the fields, then read required flow (liters/hour), required flow (us gallons/hour) and rated flow to buy (liters/hour) in the result panel. The answer updates as you type, and you can press Calculate or Enter to refresh it. Use “Copy link” to share your exact numbers with someone else.
What does the Aquarium Filter Flow Rate Calculator calculate?
Pump or filter flow you need for the tank size and turnover you want. It returns required flow (liters/hour), required flow (us gallons/hour) and rated flow to buy (liters/hour) from the 3 values you provide.
What values does the Aquarium Filter Flow Rate Calculator start with?
It opens with water volume 200 liters, turnovers per hour 6 x per hour and flow lost to media and tubing 30 % so you can see a working result straight away. Replace them with your own numbers, or press Reset to return to these starting values.
Is the Aquarium Filter Flow Rate Calculator free and private?
Yes. It is free, needs no account, and runs in your browser, so nothing you type is sent to or stored on our servers. See the Privacy Policy for details.
Can I rely on the Aquarium Filter Flow Rate Calculator for medical or health decisions?
Treat the result as a well-rounded estimate. Real situations often have details a general calculator cannot know, so confirm medical or health decisions with a qualified professional. See the Disclaimer for more.