Opinions appreciated: check valve vs anti-siphon holes in overflow returns

[Myka]

Originally Posted by fishytime

In my case it's not bad design..... I do my water changes by siphoning from the display most of the time.... Siphon break holes and check valves help keep more water in the display so I can siphon out more crap....

I do this too, but in my case, after siphoning 10 gallons out I turn the return pump on the empty the sump so I can remove another 5 gallons from the display without the corals being out of the water very long.

Originally Posted by cuz

Also don't forget the other end of things, Make sure your display can hold the volume of water your return pump will push up if the drains ever did become blocked!!

I have an "emergency" drain for just that purpose.

Originally Posted by outacontrol

I did all of the above [...] Why only have one safety in place when I can have multiple.

I agree. Although there is a difference between redundancy and superfluency. Knowledge in cause and effect will define the difference.