Flow rate thru a refugium/sump?

[jetfixr]

I have heard that the optimum flow rate thru a refugium is 3-5x, problem is I am not sure what that is based upon. Is that 3-5x the total system volume or just 3-5x turnover on the water in the sump/refugium only? If I am running a 90g tank with a 40g refugium/sump what should my return pump be running at?

[Henry Bowman]

The lower listed recommendations are referring to total tank volume. In your case that would be 3-500 gl per hour

[JPA]

My opinion is make it as fast as your sump/pump can handle without micro bubbles. I don't really see any benefit difference to 3 versus 300 as long as it doesn't take away from the display.

Joe