← Back to utilities
Filter Flow Calculator
Choose a filter that matches your tank. Flow should turn the whole tank over several times an hour — more for heavy stocking.
Flow rates on filter boxes are measured without media. Expect 30–50% less in real use with sponges and ceramics — add a flow divider or point the outlet at the glass if it's too strong.
Recommended Flow
Target Turnover
6× / hour
whole tank per hour
Flow Range
600 – 800 L/h
filter rating
Heads-up: flow ≠ filtration quality. A slightly slow filter with good media beats a fast one with none. Aim for the middle of the range, then tune with the tank's inhabitants and plants.
Related Reading
Guides that cover this topic in depth