I redid the plumbing for my return line from my sump into my tank. I had 1/2" hard PVC
with elbows and a barbed end type flow director. I changed it to 3/4 vinyl tubing with Locline plumbing and 2 locline pipes with flow directors. This increased my flow rate which is great. I have a mag7 pump with head height of 4feet the vinyl tubing is about 5feet MagDrive Flow Chart
Based on this calculator 4' is 480gph and 5' is 420gph
The problem I am experiencing is it seems as if my overflow can not keep up now. the tank level gradually rises to where I am concerned that the tank may overflow so I turn off my pump. This is my overflow New Acrylic Overflow Box and Skimmer Box for Saltwater Aquariums
It is rated to handle 700 gph
on a 75g tank with a mag7 and 500gph on a 55g tank with a mag5. I have a mag7 on a 46g tank with less surface area I am wondering if this is the problem. that I have too much flow for my surface area being so small? So my tank fills faster because it is smaller and my overflow box is not draining fast enough. I dont understand why my overflow box just does not drain faster? I really would hate to have to restrict the flow on my return pump? Help!!!