Return pump calculation

[nanomania]

Total tank volume = 300 liters
I have an Eheim compact 1000lph and 2000lph

From sump to tank, the distance is 4feet.

How much flow is better, 3x or 5x i personally don't prefer more than 5x as iv never had great results if i go above that.

My setup is:
Back sump tank at the bottom (130l) already running since a year

&

Attaching 2 new top tanks

1) 108l display
2) 61l display refugium

 

[laverda]

I find 5 times works well. Any less and I get stagnant areas in the sump. A lot depends on the design of you sump too.

 

[nanomania]

I find 5 times works well. Any less and I get stagnant areas in the sump. A lot depends on the design of you sump too.

Mine is a non skimmer setup, personally i have never liked skimmers. Thats why im confused between 3x and 5x, as its going to be a multiple setup.