Return Pump & Flow

George Behney

New member
I have a 75 main and a 40 gallon sump including the fuge. I received a Coralife 1740-p (external pump) that I am using as the return. I built a manifold system that runs along the top parameter of the inside of the tank and down the back of the tank. Using the Head Loss Calculator (and substituting the Mag 24 in place of the Coralife, as it is not an option on the calculator) I figure that my flow rate is just over 700 gph. I am curious if this is simply to much flow? By the way I am not using any other power heads at this point.

The main reason I ask is that I am having a micro bubble problem.

From everything I have read this should be OK flow rate???

If this is not OK can you recommend a return pump for me and power heads, should I need them.

Thanks for any help you can provide.


New member
if it's 700 GPH that should be fine, which is around 6 times total turnover. A lot of times if there are micro bubbles it's from a pinhole leak in the plumbing letting air in or from the skimmer return. You definitely could use powerheads as well if you think you need more flow.