Back siphon risk?

[lmm1967]

Does a KH director / doser need to be physically higher than water level in order to prevent back siphon risk?

I have a COMPLETELY dry space under my tank and I would love to install my KHD & Maxi doser (used for top off) under the stand but it would end up lower than the water level in my sump (sump is NOT under the tank).

 

[lapin]

If the output hose of any device is not in the water it will not back siphon.

 

[canadianeh]

How about output from emergency drain and reactors? Do they need to be above water or can they be in the water.

 

[lapin]

I have all of them above water. You could have them in the water in most instances. It depends on what your location is and how they are fed. If water goes from - pump in sump - to reactor - then back to sump, then it does not matter.
If your emergency drain is in the water then it must be able to clear all air to become full siphon. You dont want it too far under water. I have mine above water so if I hear splashing I know something is amiss.

Im sure there are other instances I cant imagine right now where in water might not work.

 

[vetteguy53081]

Drill hole and insert tube to create a siphon break

 

[AZMSGT]

Don’t the rollers on both style dosers pinch the line shut to keep it from siphoning or draining?

 

[Ditto]

It does pinch the line shut but like anything could wear over time, and would think because of this the recommendation would be above the water line.

 

[lmm1967]

Always keep one end of the line out of water - I can do that - and all outputs above sump water line - I can do that as well.

I guess once I thought about it a little more - and saw a few replies here - I finally realized I already knew the answer.