Check valves for 1/2" or 3/4" Vinyl Tubing?

[daplatapus]

I hope I don't come across as a pessimist here, but there is something about using a check valve for safety that inherently scares me. They are completely prone to failure. They rely very much on being, and staying, clean. After looking at my 9 month old tank, nothing is clean. There's tiny little spiroid worms and calcareous thingys everywhere. I can't see how a check valve could possible work after just a couple months hooked into my system. And part of the problem with check valves is you don't know they're going to fail until that one time you need them most and they stick.