Help!!!!! With my overflow

[chillea]

I have a 56 gallon tank and previously pump running 300 gph I upgraded my pump to a mag 7 and it was too much for the overfiow so i wanted to install a ball valve on the mag 7 and when I turned off the pump my overflow has more water and also in the wet to dry where the blue balls i have a lot of water. my question is how to remove the water?

 

[Reefing Madness]

 

[zemuss]

I am not following. You turned the pump off and water is still in the overflow? You also have more water in the sump? Correct?

First what is the flow rate of a MAG7? What is the flow rate of the overflow? You need to keep the pump under the flow rate fo the overflow. For instance if the flow rate for the overflow is 500gph then the pump should be below this number never above or you can cause an over flow and water on the floor.