RSR xl 300 return pump flow??

[rsaylor3]

Ok, I'm somewhat new to all of this and have a question for the experts! I have a Varios 6 return pump. I set up the tank over the weekend and followed the directions of getting about 6 inches of water in the sump when filling the tank. I have been running the pump at it's lowest setting with no issues and dead quiet operation. I decided to try the pump at leveled 2 for increased flow. Even with the valve completely opened the system can't keep enough water in the chamber for the return pump and it's sucking air.

Two questions, first do I need to add more water to the system if running at the higher flow rate? Second, do I even need to worry about more flow through the sump and should I just leave it at the lowest setting?

I have two reefwave 25's in the tank for flow as well.

Thanks everyone for your responses, just trying to get this right

 

[Montiman]

In theory the water level in the display tank should be the same regardless of the pump speed. In reality I have seen the water level in the main display rise slightly when increasing the return pump size. This would explain why the water level is low. It shifted to the display. I would first try adding more water and then checking from there.

Another related question is with the valve all the way open what is happening? If the drain can't keep up you should see no bubbles coming from the valved drain and alot coming from the non valved emergency drain. If the water level has simply increased in the display then when the valved drain is all the way open you will periodically see bubbles coming from the main drain and nothing coming from the secondary non valved drain.