Discus water flow rate?

[Gebhardt]

Hi

In a discus tank with a sump how do one calculate water flow rate?
Tank 680lit and sump 95lit.

Thanks

[Jhhnn]

I take it you're trying to determine the right size of pump.

There are other variables to be considered, like stocking levels and the presence of other filtration methods. In general, a pump that delivers ~4X the volume of the tank per hour is recommended, iirc. Some would say more. Discus don't need or enjoy strong currents, something that needs to be accounted for, as well.