As a suggestion if you have the room - I converted my wet/dry to a pure sump and am using a cheap rubbermaid type container from Walmart as my fuge (which sits right next to the sump. The tank drains to a "T" with 2/3 of the water going to the sump and 1/3 to the fuge. I drilled holes near the top on the side of the "fuge" that is next to the sump and using PVC and o-rings it overflows into the sump.
The "2/3rd" water from the tank goes into the first section of the sump (former wet dry) which has mechanical filtration (poly filter, carbon, etc.) up high with live rock on the bottom. Water then flows into the second compartment where the skimmer sits and where the fuge overflow water comes. This way the skimmer is still getting some tank water that has not been through the poly filter, carbon, etc. I have a piece of plexiglass separating this second compartment into two small compartments. The return pump to the tank (Mag 7) is in the second part of this compartment.
This set up provides protection in case of a power failure and has proven to work good. And best of all it was very inexpensive.