Configuring Siphon Break After Changing Return Nozzle

Fish_Fry

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TL;DR

I changed my return nozzle and when my return loses power my sump comes dangerously close to overflowing before the siphon breaks. If I adjust the nozzles upward (so the siphon breaks sooner) I get too much surface agitation.

Deets:

I have a 75 gallon IM tank and decided to replace the return with VCA random flow generator*. Instead of a narrow, horizontal flow, the new nozzles are wide circles. As such I’m getting a lot more backflow before the siphon breaks.

It’s not overflowing the sump, but it’s getting within an inch or two. I’m worried if the nozzle were to get bumped slightly, I wouldn’t have any margin of error. I might be able to lower the water level in the sump, but I don’t think it would be enough.

If I raise the return nozzles I get too much surface agitation. How is everyone else handling this? Anyone have any cool designs? I have seen people drill a hole in the return to break the siphon sooner, but I’m worried it would clog. Would multiple holes help?

Thanks
T



* Lesson 1 sometimes leave well enough alone and don’t mess with things.
 

tbrown

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Any reason you can't just remove some water from the sump and adjust your ATO top off sensor to the new running level?

Another option is to drill a hole in the side of the return piping to create a new siphon break.
 

tbrown

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Another option is to add a PVC coupling between the LocLine and the bulkhead and drill that.
 

painter1982

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I put an all plastic check valve in mine. Seems to work. It has unions on it and I clean it when I clean my return pump.
 

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