drill holes in return line?

Reverend Reefer · 05/07/2010, 07:17 PM

what do people mean when they say they drill holes in the return line to the display from the sump? they say it has to do with breaking the siphon. what does this mean? where do i drill the holes? near the return pump or at the top as it goes over into the display? if i drill holes on the pipe going back up to the DT, won't water come out of the pipe via the holes?

JBrown · 05/07/2010, 07:20 PM

Your going to want to drill a hole just above the water line so in the event of a power outage your return line does not create a siphon draining your tank in the process

Jocephus · 05/07/2010, 07:22 PM

When the power goes out, the lowest pipe in your tank is where the water will drain to. Until it sucks air, water continues down into your sump and if your sump is small, onto your floor. When people advocate drilling holes in return lines what they are trying to do is to break the natural syphon that happens when you lose power. The holes should be drilled just below the rim of the tank ON THE INSIDE. If you drill the lines before the water would spill into the tank, the water will shoot all over. Make sure the holes will only squirt water into the tank. Make sense?

Good luck!

Joe

KafudaFish · 05/07/2010, 07:25 PM

The hole is very small like 1/16" diameter so very little water flows out. Some people put two in that way if one is blocked with say a snail the other will allow air in breaking the siphon. It is just like when you put your finger over a straw end and lift out liquid. Remove the finger, air enters and liquid flows.

So how do you know if you need one? If your sump can handle all the water that returns when the power is off then no. If it would overflow then yes.

I have also seen people with them below the water line. A gallon or a few may sipon back but once the hole is exposed to the air it breaks.

zoolan70 · 05/07/2010, 07:44 PM

I just drilled two 1/16" holes into the "bottom" of the elbow where the return line transitions from vertical (up through the overflow) to horizontal (Loc-line). I also have my return lines spraying right at the water's surface, just in case.

Drjusc00 · 05/07/2010, 09:06 PM

Good idea!!

05/07/2010, 07:17 PM	#1
Reverend Reefer Registered Member Join Date: Dec 2008 Location: Toronto, ON, Canada Posts: 883	drill holes in return line? what do people mean when they say they drill holes in the return line to the display from the sump? they say it has to do with breaking the siphon. what does this mean? where do i drill the holes? near the return pump or at the top as it goes over into the display? if i drill holes on the pipe going back up to the DT, won't water come out of the pipe via the holes? __________________ - Rev. Tank: 65G glass 48" long tank; Sump/Fuge: 30G. Lighting: LEDs+single T5 strip. Maintenance: ATO Kalkwasser + 10% weekly WC, daily feedings LPS+Softies dominated.

Similar Threads
Thread	Thread Starter	Forum	Replies	Last Post
Where to drill holes in return for anit-siphon?	DGlove904	New to the Hobby	12	09/10/2009 02:36 PM
Drill Holes for Return Pump?	huskysglare1	Reef Discussion	4	06/08/2009 08:05 PM
return line hole location ??	tl_vang86	Nano Reefs	5	08/31/2007 08:09 PM
Drilling hole in return	jlfritsche	Do It Yourself	1	05/07/2006 05:56 PM
question about drilling siphon hole in return plumbing	Cox	Do It Yourself	4	04/21/2006 03:57 PM

05/07/2010, 07:20 PM	#2
JBrown Registered Member Join Date: Jan 2003 Location: Brockport NY Posts: 457	Your going to want to drill a hole just above the water line so in the event of a power outage your return line does not create a siphon draining your tank in the process

05/07/2010, 07:22 PM	#3
Jocephus Registered Member Join Date: Jun 2007 Location: Dover, DE Posts: 995	When the power goes out, the lowest pipe in your tank is where the water will drain to. Until it sucks air, water continues down into your sump and if your sump is small, onto your floor. When people advocate drilling holes in return lines what they are trying to do is to break the natural syphon that happens when you lose power. The holes should be drilled just below the rim of the tank ON THE INSIDE. If you drill the lines before the water would spill into the tank, the water will shoot all over. Make sure the holes will only squirt water into the tank. Make sense? Good luck! Joe

05/07/2010, 07:25 PM	#4
KafudaFish Cyprinius carpio Join Date: Mar 2004 Posts: 4,496	The hole is very small like 1/16" diameter so very little water flows out. Some people put two in that way if one is blocked with say a snail the other will allow air in breaking the siphon. It is just like when you put your finger over a straw end and lift out liquid. Remove the finger, air enters and liquid flows. So how do you know if you need one? If your sump can handle all the water that returns when the power is off then no. If it would overflow then yes. I have also seen people with them below the water line. A gallon or a few may sipon back but once the hole is exposed to the air it breaks.

05/07/2010, 07:44 PM	#5
zoolan70 Registered Member Join Date: May 2008 Location: Lakeville, MN Posts: 248	I just drilled two 1/16" holes into the "bottom" of the elbow where the return line transitions from vertical (up through the overflow) to horizontal (Loc-line). I also have my return lines spraying right at the water's surface, just in case.

05/07/2010, 09:06 PM	#6
Drjusc00 Registered Member Join Date: Apr 2010 Posts: 141	Good idea!!