As far as the 1/8" hole siphon brake theory for canisters (good idea). While we are on that subject..
You can also do the same thing to a freshwater sump overflow box siphon tube if you rather have a deep siphon rather then a skimmer which serves no purpose on a freshwater sump system in fact is a real hindrance in picking up debris.
And if you want an instantaneous siphon brake so that the amount of water between the waterline and the 1/8" hole doesn't end up on the floor, about 2-5 gallons. You can take an additional step.
Using a garden drippier hole punch tool, punch two holes just above the water line at the tank rim level of both the intake and outflow lines and install garden drippier access plugs nipple into the two punched holes and then depending upon the distance between your intake and out flow lines install one piece section of aquarium airline one each garden drippier nipple. Now when you start your pump and its running if there is a power failure and the pump stops the pump line immediately fills with air and immediately brakes the siphon on the other linen no water loss/flood. And once the power come back on the pump line fills with water and re-primes the siphon line establishing siphon starting the entire system automatically.