[Reefmedic79]

To Reef Central

No experience with the CPR stuff, but it sounds like it should be ok.

Your Fluvals can be used empty to turn over water, but the won't create a lot of flow for a reef tank. You could possibly have issues with nitrates if you put media in the filters. A Mag 12 will get alot of flow to the tank. IMO, they are better suited submerged, but will put a lot of heat into the tank as well. They tend to run quieter when submerged.

Drilling a small hole just below the waterline of the siphon pipe to the over flow will break the siphon when the tank starts to drain preventing all you water from draining out. You just need to leave enough space in your sump to hold the couple extra gallons that will siphon out until it breaks.