Hole in return pipe?

basssnake · 09/01/2008, 01:40 PM

My return pipe inside of my overflow box has a hole drilled i assume for anti siphoning. The thing is it goes at a angle toward the ceiling and the guy that had the tank before used a mag4 or 5 pump and i will be using a iwaki rxlt40(1200gph). I don't want it to spray out and onto the ceiling or floor. The hole will be sitting under the water in the overflow and is pointed at the pipe for the drain. Should i reverse this so the hole is at the bottom or rebuild the pipe? Or should i leave it as it is and is there any concern of water spraying out? The hole is about 3/16" or so.

boilermaker1 · 09/01/2008, 01:45 PM

It is for anti drain back, the easiest thing to do would be to take a piece of PVC and glue it to the pipe just above the hole as a "shield" so that it doesnt shoot upwards.
Or you can plug it and drill another.

jakkalofv · 09/01/2008, 01:58 PM

silicone a piece of air line tubing in the hole and point it downward with the end slightly below the water level

AZDesertRat · 09/01/2008, 03:29 PM

The safest thing is eliminate it altogether and simply make sure your return is just slightly below thexsurface so it breaks suction quickly in a power outage. Drilled holes wil plug and fail and are a false sense of security, air gaps don't fail and are the most foolproof method of backflow prevention.

basssnake · 09/01/2008, 03:55 PM

How could i plug the hole? So, i should do something with the hole then? What if i just put it at the bottom? There is already a hole in the locline anyways.

basssnake · 09/01/2008, 04:01 PM

The return will actually be above the water surface(the pipe anyways, the loc line will be underwater). Please explain more, thanks

AZDesertRat · 09/01/2008, 05:03 PM

If the LocLine is just below the surface the water will never drop below the level of the LocLine once its exposed to air. I always maintain freeboard or room in my sump to contain that 1" or so of water at all times even when its full. In my case with a 100G tank and 30G sump it amounts to about 4 gallons of water which is easily held in the sump.
I would plug the hole or install a new piece of pipe, putting the hole at the bottom would allow water to backsiphon down to whatever level the hole is at.

basssnake · 09/02/2008, 08:12 AM

I just ended up reversing the pipe so that the hole is near the bottom. So, if i understand correctly, that is what you are saying was ok to do?

AZDesertRat · 09/02/2008, 09:43 AM

No. With the hole submerged water will backsiphon to that level when power is off. If you have an internal overflow it will drain th eentire overflow box and if it is like some and not sealed perfectly possibly the entire tank. If it is a hang on overflow it will drain the overflow box. I would leave the hole on top and plug it or get a new piece of PVC without a hole.

basssnake · 09/02/2008, 02:01 PM

I have already glued the pvc and everything in place. I do have parts to build the new pvc inside the overflow, but i would have to buy all new parts to build my U shaped piece to hold the loc line. So, i should pull it a second time and redo it for a third time? this is a bummer if so......lol.......but, i don't want a problem. The overflow so far hasn't drained any water in it and i have the tank filled about 1/3 of the way. It is a internal overflow. Let me know if this is a really must do situation, and if so, then i guess i can redo. Thanks for your help so far and thanks for continuing to help me

AZDesertRat · 09/02/2008, 03:03 PM

Calculate the additional volume of the overflow box and add it to the 1" to 2" that will backsiphon in a power outage (depending on what level your LocLine is placed in the tank). Make sure you always maintain that much space in your sump at all times, plus a few more gallons just as a safety factor. I know I flow just short of 4 gallons back but i always maintain 8 gallons of freeboard just as a fudge factor.

basssnake · 09/02/2008, 06:36 PM

Well, the tank is acrylic so i assume that the overflow box is fused to the acrylic(the overflow box looks like black acrylic) and if so, shouldn't never leak. But i am not certain it is fused. I really don't see any silicone i don't think. Anyways, my tank is a true 180 gallon and my sump is a 100 gallon rubbermaid stock tank, which i should have about 3 inches of room in it and the stock tank drains into a 45 gallon glass sump tank( i am using as a refugium) and that tank has about 6 inches of room or so. So, maybe it would hold? I could take it apart and redo(not extremely laboring, just i am getting sick of the plumbing work,lol).

AZDesertRat · 09/02/2008, 07:43 PM

Sounds like you have plenty of room.

basssnake · 09/02/2008, 08:04 PM

Should i just leave it alone and not redo it then?

AZDesertRat · 09/02/2008, 08:46 PM

I wouldn't think your overflow would hold more than 2 or 3 gallons and it sounds like your sump/fuge will easily hold that amount of extra water.

09/01/2008, 01:40 PM	#1
basssnake Registered Member Join Date: May 2006 Location: Kansas Posts: 838	Hole in return pipe? My return pipe inside of my overflow box has a hole drilled i assume for anti siphoning. The thing is it goes at a angle toward the ceiling and the guy that had the tank before used a mag4 or 5 pump and i will be using a iwaki rxlt40(1200gph). I don't want it to spray out and onto the ceiling or floor. The hole will be sitting under the water in the overflow and is pointed at the pipe for the drain. Should i reverse this so the hole is at the bottom or rebuild the pipe? Or should i leave it as it is and is there any concern of water spraying out? The hole is about 3/16" or so.

09/01/2008, 01:45 PM	#2
boilermaker1 Registered Member Join Date: Jul 2005 Location: Chantilly, VA Posts: 784	It is for anti drain back, the easiest thing to do would be to take a piece of PVC and glue it to the pipe just above the hole as a "shield" so that it doesnt shoot upwards. Or you can plug it and drill another.

09/01/2008, 01:58 PM	#3
jakkalofv Registered Member Join Date: Aug 2007 Location: the triangle, NC Posts: 98	silicone a piece of air line tubing in the hole and point it downward with the end slightly below the water level

09/01/2008, 03:29 PM	#4
AZDesertRat Moved On Join Date: Jan 2002 Location: NW Phoenix Posts: 16,621	The safest thing is eliminate it altogether and simply make sure your return is just slightly below thexsurface so it breaks suction quickly in a power outage. Drilled holes wil plug and fail and are a false sense of security, air gaps don't fail and are the most foolproof method of backflow prevention.

09/01/2008, 03:55 PM	#5
basssnake Registered Member Join Date: May 2006 Location: Kansas Posts: 838	How could i plug the hole? So, i should do something with the hole then? What if i just put it at the bottom? There is already a hole in the locline anyways.

09/01/2008, 04:01 PM	#6
basssnake Registered Member Join Date: May 2006 Location: Kansas Posts: 838	The return will actually be above the water surface(the pipe anyways, the loc line will be underwater). Please explain more, thanks

09/01/2008, 05:03 PM	#7
AZDesertRat Moved On Join Date: Jan 2002 Location: NW Phoenix Posts: 16,621	If the LocLine is just below the surface the water will never drop below the level of the LocLine once its exposed to air. I always maintain freeboard or room in my sump to contain that 1" or so of water at all times even when its full. In my case with a 100G tank and 30G sump it amounts to about 4 gallons of water which is easily held in the sump. I would plug the hole or install a new piece of pipe, putting the hole at the bottom would allow water to backsiphon down to whatever level the hole is at.

09/02/2008, 08:12 AM	#8
basssnake Registered Member Join Date: May 2006 Location: Kansas Posts: 838	I just ended up reversing the pipe so that the hole is near the bottom. So, if i understand correctly, that is what you are saying was ok to do?

09/02/2008, 09:43 AM	#9
AZDesertRat Moved On Join Date: Jan 2002 Location: NW Phoenix Posts: 16,621	No. With the hole submerged water will backsiphon to that level when power is off. If you have an internal overflow it will drain th eentire overflow box and if it is like some and not sealed perfectly possibly the entire tank. If it is a hang on overflow it will drain the overflow box. I would leave the hole on top and plug it or get a new piece of PVC without a hole.

09/02/2008, 02:01 PM	#10
basssnake Registered Member Join Date: May 2006 Location: Kansas Posts: 838	I have already glued the pvc and everything in place. I do have parts to build the new pvc inside the overflow, but i would have to buy all new parts to build my U shaped piece to hold the loc line. So, i should pull it a second time and redo it for a third time? this is a bummer if so......lol.......but, i don't want a problem. The overflow so far hasn't drained any water in it and i have the tank filled about 1/3 of the way. It is a internal overflow. Let me know if this is a really must do situation, and if so, then i guess i can redo. Thanks for your help so far and thanks for continuing to help me

09/02/2008, 03:03 PM	#11
AZDesertRat Moved On Join Date: Jan 2002 Location: NW Phoenix Posts: 16,621	Calculate the additional volume of the overflow box and add it to the 1" to 2" that will backsiphon in a power outage (depending on what level your LocLine is placed in the tank). Make sure you always maintain that much space in your sump at all times, plus a few more gallons just as a safety factor. I know I flow just short of 4 gallons back but i always maintain 8 gallons of freeboard just as a fudge factor.

09/02/2008, 06:36 PM	#12
basssnake Registered Member Join Date: May 2006 Location: Kansas Posts: 838	Well, the tank is acrylic so i assume that the overflow box is fused to the acrylic(the overflow box looks like black acrylic) and if so, shouldn't never leak. But i am not certain it is fused. I really don't see any silicone i don't think. Anyways, my tank is a true 180 gallon and my sump is a 100 gallon rubbermaid stock tank, which i should have about 3 inches of room in it and the stock tank drains into a 45 gallon glass sump tank( i am using as a refugium) and that tank has about 6 inches of room or so. So, maybe it would hold? I could take it apart and redo(not extremely laboring, just i am getting sick of the plumbing work,lol).

09/02/2008, 07:43 PM	#13
AZDesertRat Moved On Join Date: Jan 2002 Location: NW Phoenix Posts: 16,621	Sounds like you have plenty of room.

09/02/2008, 08:04 PM	#14
basssnake Registered Member Join Date: May 2006 Location: Kansas Posts: 838	Should i just leave it alone and not redo it then?

09/02/2008, 08:46 PM	#15
AZDesertRat Moved On Join Date: Jan 2002 Location: NW Phoenix Posts: 16,621	I wouldn't think your overflow would hold more than 2 or 3 gallons and it sounds like your sump/fuge will easily hold that amount of extra water.