ABSOLUTELY NOT!
Check valves have no place in a reef tank and give you a false sense of security. Its not a matter of if but when they will fail and it will happen, usually at the worst possible moment.
Design your return so it is just below the surface and only a slight, easily calculated amount of water will flow back to the sump before the return is exposed to atmosphere and you have the best, most foolproof method of protection there is, an air gap.
Always keep that amount of freeboard or extra room in the sump and you never have to be concerned about a flood and can sleep soundly at night.
My 60"x18"x23", 100G display has a 30G sump. My returns are 3/4" below the surface. 60x18x.75/231= 3.5 gallons maximum that can possibly backsiphon. My sump is 30 gallons so an extra 3.5 gallons of space is no problem, in fact my skimmer works best when the level is lower so I always maintain closer to 8-9 gallons of empty space even when fully topped off so it is never an issue.
Check valves and drilled holes fail, there is no getting around it. You can clean it 5 minutes ago and a grain of sand sticks on the valve seat defeating it the first time the power goes off. It does not have to be a catastrophic failure, even a trickle will flood in time. Same with drilled holes in the return, a small fish, snail, frozen food, algae, flake food, an anemone, anything can and will defeta the hole or holes and your safety is gone. They cannot plug up an air gap and water cannot jump uphill so you have a foolproof system period.
