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

[sphelps]

I agree with Myka, the need for siphon breaks or check valves is a result from bad design. I think the majority of experienced people will agree you shouldn't rely on such things. However you may want to add them to prevent full back back flow all the time but your system should still be able to handle the back flow if the breaks or valve fail. If this were the case check valves would be a better option than break holes as they require more maintenance being that they are often plagued with algae growth.