Choosing a external overflow box.

Jackie Blue · 04/27/2009, 11:46 PM

Today was the day. We have all read about people who just walk over to their tank and to their horror realize that there is water where water should not be. Everything is in buckets and a tote now. I have found and bought another 75 gal fish tank already and it is sitting in my garage (craigs list is a god send). However this tank does not have an internal overflow so I need an external overflow.

Here is what I have found so far, if it sucks please let me know.

http://www.drsfostersmith.com/produc...m?pcatid=18358

I am looking to get the PF-1000 since it is not on backorder and has to outlets, it's cheap, and it can get here in 2 days with express shipping and I would still pay under 100 dollars.

If there is anything better that won't cost an arm and a let, and that can get here in a short amount of time please let me know.

Thanks in advance,

Jack

Jackie Blue · 04/27/2009, 11:58 PM

BTW if anybody has any good ideas or if there are any proven ways to go about plumbing a 75 gall. that is not reef ready feel free to chime in. Pictures would be most lovely.

sjm817 · 04/28/2009, 06:12 AM

Since it is sitting on the garage floor, drill it. Its easy. You can get everything you need in a kit with instuctions from http://www.glass-holes.com

Jackie Blue · 04/28/2009, 09:01 AM

Ok it's going to get drilled, now all I have to do is figure out where to put the box and return or returns.

Uncle Salty 05 · 04/28/2009, 09:03 AM

I like these personally.

http://www.marinedepot.com/ps_Aquari...boxes_cpr.html

They cost more but are ready for an aqualifter and are very quiet and never fail.

THE ROOK · 04/28/2009, 11:06 AM

I believe there is an install video on glass-holes website. They're kit is pretty popular & I'd buy one in a second if needed.

Jackie Blue · 04/28/2009, 11:26 AM

That second has come and gone, I have the 1500 gph one that should show up thursday, thanks everybody this whole bit would of been much more unpleasant without you guys.

sjm817 · 04/28/2009, 01:38 PM

You made a good choice. Good luck with the new setup.

DarG · 04/28/2009, 02:42 PM

Quote:

Originally posted by Uncle Salty 05
I like these personally.

http://www.marinedepot.com/ps_Aquari...boxes_cpr.html

They cost more but are ready for an aqualifter and are very quiet and never fail.

Yeah ... they never fail unless/until the aqualifter or whatever other means you use to keep the air from accumulating fails. Because of the design, the water velocity alone is not sufficient to keep air from accumulating and therefore you have to use an aqualifter or other suitable means to keep the air from accumulating and the unit from losing siphon.

Properly designed U-tube overflow is the way to go if one is going to use a HOB overflow. They do not require a secondary pump or means to clear air from the U-tubes, the water velocity through the U-tubes takes care of it. No secondary device to rely on, less chance of failure. Personally, I think Lifereef is the best built overflow on the market and they are properly designed, period.

MatthewLaw · 04/28/2009, 03:11 PM

i am using two Eshopps 800s on my 50g and 60g tanks. both overflows work excellently and no issues!

Uncle Salty 05 · 04/29/2009, 06:10 AM

Quote:

Yeah ... they never fail unless/until the aqualifter or whatever other means you use to keep the air from accumulating fails. Because of the design, the water velocity alone is not sufficient to keep air from accumulating and therefore you have to use an aqualifter or other suitable means to keep the air from accumulating and the unit from losing siphon.

Malarki!
A U tube is just as likely if not more so to accumulate air bubbles.
The CPR's are quieter, better looking and can move more water.
An aqualifter with a check valve should be used on a U tube just like the CPR's or eventually you will lose siphon.

sjm817 · 04/29/2009, 06:43 AM

A U Tube will never accumulate air if the overflow is designed properly and adequate flow moves through it. If will run indefinitely without failure. You will not eventually lose siphon. People have used them for many years on end without an issue.

A CPR on the other hand ALWAYS accumulates air and must use an external pump to remove it. A failed pump is just one of several failure scenarios. A clogged air nipple is another very common one.

The Lifereef U Tube overflows have a reputation for being incredibly reliable. The CPRs have a reputation for high failure. They both earned the respective reputations from user experience.

Uncle Salty 05 · 04/29/2009, 06:54 AM

Well I must just be incredibly lucky on the CPR's and incredibly unlucky with the U tubes because my CPR has been running for over 10 years without a single failure and my tank with a U tube has to have the siphon re-started about every week or two.

Believe half of what you see and none of what you "hear".

sjm817 · 04/29/2009, 07:38 AM

You have been very lucky with your CPR. Glad to see it has worked for you. Many are not so fortunate. Your U tube is either a poor unit or has inadequate flow thought it.

My CPR failed twice in 3 months. My Lifreef was flawless in the 2 years I ran it and would have stayed that way If I still ran it.

Use experience and opinion will obviously vary. Design principles and the physics of a siphon do not.

Uncle Salty 05 · 04/29/2009, 07:51 AM

Quote:

You have been very lucky with your CPR. Your U tube is either a poor unit or has inadequate flow thought it.

Quote:

My CPR failed twice in 3 months. My Lifreef was flawless in the 2 years I ran it and would have stayed that way If I still ran it.

Quote:

Use experience and opinion will obviously vary. Design principles and the physics of a siphon do not.

Conversely perhaps your CPR problems were due to operator error or an undersized unit?
Both types are still available, if the CPR were as flawed as you claim I doubt that would still be the case.
I am not trying to be argumentative but I hate to see newbies told to avoid what I see as an excellent product.
Both work about the same in my opinion but I prefer the look, volume and reliability of the CPR.

sjm817 · 04/29/2009, 07:55 AM

The failure both times was a clog in the air nipple in the inside of the box. This is a very common failure scenario.

Aquarist007 · 04/29/2009, 08:10 AM

Make your own overflow---I did for 30 bucks: the price of an hob filter body replacement and a 3/4 inch u tube.

DarG · 04/29/2009, 08:14 AM

Quote:

Originally posted by Uncle Salty 05
Well I must just be incredibly lucky on the CPR's and incredibly unlucky with the U tubes because my CPR has been running for over 10 years without a single failure and my tank with a U tube has to have the siphon re-started about every week or two.

NOT ALL U-TUBE BASED OVERFLOWS ARE THE SAME.

AGAIN, a properly designed U-Tube overflow, properly applied, will retain siphon while running and when power fails. I dont understand why you would continue to use your U-Tube overflow if it loses siphon every week or two but that's another subject.
Its either not designed properly or your flow rate is too low.

A properly designed U-Tube overflows only requirement to keep air from accumulating is a minimum flow rate through the U-tube, depending on the diameter of the U-tube. Water velocity, on its own, keeps air bubbles from accumulating in the tubes.

Using the Lifereef overflows as an example ... I highly doubt that you would find one user report a failure of the unit to retain siphon that was not due to user error (too low a flow rate through a dual unit for example). On the other hand, there have been more than a few reports of tank overflows with the C-channel (weir) style overflows in this forum alone ... either due to failed secondary pump (ie aqualifter) or clogged air fitting.

And your closing comment ... "Believe half of what you see and none of what you "hear" ... would be fair if it werent for the fact that it assumes an awful lot. I have a CPR overflow in the garage collecting dust.

The fact of the matter is that an overflow that relies on a secondary pump to retain siphon adds another variable that can cause failure. And failures of this style overflow are not uncommon because of that fact (as well as the potential for the air fitting clogging from buildup or a blockage). It is simply common sense.

A properly designed and applied U-Tube style overflow requires NO secondary pump or other device to clear the air from the U-tubes, no air fitting to potentially clog and far less chance of failure. I use the Lifereef and that is all I will use for several reasons but there are other, less expensive, U-Tube type overflows that are also reliable ... they wont lose siphon during operation or when the pump is shut down, they dont need secondary pump to clear air ... no secondary device needed to operate properly, no air nipple to clog = much less chance of failure. It's common sense and its proven in application based on the reports of failures by users of the weir style overflows.

sjm817 · 04/29/2009, 08:16 AM

And the OP already decided to drill the tank anyway. That will work too LOL.

Aquarist007 · 04/29/2009, 08:20 AM

Quote:

Originally posted by DarG
NOT ALL U-TUBE BASED OVERFLOWS ARE THE SAME.

AGAIN, a properly designed U-Tube overflow, properly applied, will retain siphon while running and when power fails. I dont understand why you would continue to use your U-Tube overflow if it loses siphon every week or two but that's another subject.
Its either not designed properly or your flow rate is too low.

A properly designed U-Tube overflows only requirement to keep air from accumulating is a minimum flow rate through the U-tube, depending on the diameter of the U-tube. Water velocity, on its own, keeps air bubbles from accumulating in the tubes.

Using the Lifereef overflows as an example ... I highly doubt that you would find one user report a failure of the unit to retain siphon that was not due to user error (too low a flow rate through a dual unit for example). On the other hand, there have been more than a few reports of tank overflows with the C-channel (weir) style overflows in this forum alone ... either due to failed secondary pump (ie aqualifter) or clogged air fitting.

And your closing comment ... "Believe half of what you see and none of what you "hear" ... would be fair if it werent for the fact that it assumes an awful lot. I have a CPR overflow in the garage collecting dust.

The fact of the matter is that an overflow that relies on a secondary pump to retain siphon adds another variable that can cause failure. And failures of this style overflow are not uncommon because of that fact (as well as the potential for the air fitting clogging from buildup or a blockage). It is simply common sense.

A properly designed and applied U-Tube style overflow requires NO secondary pump or other device to clear the air from the U-tubes, no air fitting to potentially clog and far less chance of failure. I use the Lifereef and that is all I will use for several reasons but there are other, less expensive, U-Tube type overflows that are also reliable ... they wont lose siphon during operation or when the pump is shut down, they dont need secondary pump to clear air ... no secondary device needed to operate properly, no air nipple to clog = much less chance of failure. It's common sense and its proven in application based on the reports of failures by users of the weir style overflows.

Darg--in my particular diy setup if there is a power failure the siphon will continue to drain the tank since the drain is gravity fed.
It will drain the tank to a pre determined level I measured so it doesn't overflow the sump

However once the tank gets down to the set level won't the siphon break in the u-tube?
If so what would you suggest I could add to the design.

sjm817 · 04/29/2009, 08:25 AM

Capn, its a little hard to see what your DIY design looks like.
You have to be sure the U Tube is full of water when power is off. This means both ends of the U Tube must be submerged when power is off. The tank side usually takes care of itself. The drain side will need a baffle or a standpipe to keep the end submerged.

Uncle Salty 05 · 04/29/2009, 08:27 AM

Quote:

I dont understand why you would continue to use your U-Tube overflow if it loses siphon every week or two but that's another subject.

The unit is on an 55 gallon algae farm I "inherited" from my neighbor that threw in the towel, it is a single U tube on a HOB wet dry being driven by an Aqua clear 70 (400gph).

My personal experience is my weir style overflow has never failed in over 10 years and every U tube set up I have had over the years has failed at sometime.

Quote:

It's common sense and its proven in application based on the reports of failures by users of the weir style overflows.

I guess I am just lucky, maybe I will buy a lottery ticket tonight.

DarG · 04/29/2009, 09:09 AM

Overflows all continue to drain the tank until the water level in the tank gets below the edge or teeth of the internal box. Since I am not a scientist, the best I can describe a properly designed U-tube overflow and why it doesnt lose siphon when pump is shut down is due to equilibrium. Proper design between the height of the drain pipes in the outer box and/or the U-tubes in the outer box being contained in their own chamber ... so that water stops draining down to the sump BEFORE the water level in the inner and outer boxes fall to a level below the ends of the U-tubes. Again, I dont know the scientific terms or laws of physics that govern this and I dont pretend to.
Obviously there is a siphon through the utubes between the inner and outer boxes. But it has something to do with gravity and equilibrium so that the siphon stops draining water between the inner and outer boxes yet the water remains in the U-tubes ... I assume because the pressure is equalized in the tubes at a certain point BEFORE the water level drops below the ends of the U-Tubes because of an equalization of the water levels/pressures between the inner and outer boxes.

The key seems to be the U-tubes being in their own chamber in the outer box ... and/or the drain pipes to the tank being above the level of the bottom of the U-Tubes. The Lifereef has the central chamber in the outer box that the U-tubes empty into. And so do the other designs that most people seem to recommend as reliable.

Sorry, I dont know the science. But if the outer box is non chambered which just allows the U-tubes to empty into the open area and the tops of the drains are below the bottoms of the U-tubes then the siphon will continue until the Utubes empty and then obviously they wont resume siphon when power is turned back on. And I dont know if it goes beyond just that and the U-Tubes actually require their own chamber in the external box. Again, I think that all the overflows that seem to be recommended all have this dedicated chamber for the U-tubes to empty into in the external box.

And I realize that this probably doesnt help you at all because I dont know the technical side of it in order to explain it.

Which is probably why I just bought the Lifereef instead of any of the other recommended, less expensive U-tubes based on it having the absolute best reputation of all the external overflows ... this of course after learning a valuable lesson after having an aqualifter pump fail on a CPR overflow and realizing that Murphys law is bad enough without tempting it by hoping I would have better luck with a second aqualifter (and on top of that, also hoping the air fitting wouldnt clog on the CPR).

Im sure one of the more scientific minds could explain it better.

MatthewLaw · 04/29/2009, 09:13 AM

i think that is a pretty accurate description. at least it makes sense and applies when I shut off my return pump to similate a failure to ensure that everything is properly set up.

DarG · 04/29/2009, 09:28 AM

Quote:

Originally posted by Uncle Salty 05
The unit is on an 55 gallon algae farm I "inherited" from my neighbor that threw in the towel, it is a single U tube on a HOB wet dry being driven by an Aqua clear 70 (400gph).

My personal experience is my weir style overflow has never failed in over 10 years and every U tube set up I have had over the years has failed at sometime.

I guess I am just lucky, maybe I will buy a lottery ticket tonight.

Its probably not worth the debate but to me it's common sense. I have had an aqualifter pump die while using the CPR. The aqualifter can fail (and this is not what would be considered a rare occurence) and the air fitting can clog ... I have read about failed CPR overflows due to the pump failure or clogged air fitting on several occassions on this forum alone. As well as reports of failed Aqualifters in general.
So one is relying on two necessary, additional variables with the Weir style overflow.

I have never heard or read of a Lifereef overflow failing. I believe that Jeff at Lifereef has never had a report of one of his overflows failing. The design will not fail. My dual Lifereef has not failed in the two years or so that I have been using it. Obviously there are other outside variables that can potentially cause a failure that are not directly attributed to the design of the overflow itself and are outside of user error. But the weir style overflows have two additional issues that are part of the design and can directly cause failure. The secondary pump failing and the air fitting clogging. Both these things have been reported. I have had the pump fail on me personally.

I certainly dont wish for you to have any problems. But again, to me, it is common sense that these two additional variables translate to an increased risk of failure. So I personally would not and do not recommend these style overflows when I throw in my opinion on the topic. And my opinion in these cases is based on actual experience.

04/27/2009, 11:46 PM	#1
Jackie Blue Registered Member Join Date: Feb 2009 Location: Elgin, IL Posts: 333	Choosing a external overflow box. Today was the day. We have all read about people who just walk over to their tank and to their horror realize that there is water where water should not be. Everything is in buckets and a tote now. I have found and bought another 75 gal fish tank already and it is sitting in my garage (craigs list is a god send). However this tank does not have an internal overflow so I need an external overflow. Here is what I have found so far, if it sucks please let me know. http://www.drsfostersmith.com/produc...m?pcatid=18358 I am looking to get the PF-1000 since it is not on backorder and has to outlets, it's cheap, and it can get here in 2 days with express shipping and I would still pay under 100 dollars. If there is anything better that won't cost an arm and a let, and that can get here in a short amount of time please let me know. Thanks in advance, Jack __________________ How am I doing? Well I got ten fingers and toes. Current Tank Info: 120 Gallon. Custom made refugium sump 30 gallons.

04/27/2009, 11:58 PM	#2
Jackie Blue Registered Member Join Date: Feb 2009 Location: Elgin, IL Posts: 333	BTW if anybody has any good ideas or if there are any proven ways to go about plumbing a 75 gall. that is not reef ready feel free to chime in. Pictures would be most lovely. __________________ How am I doing? Well I got ten fingers and toes. Current Tank Info: 120 Gallon. Custom made refugium sump 30 gallons.

04/28/2009, 06:12 AM	#3
sjm817 On Yer left! Join Date: Sep 2004 Location: Northern VA Posts: 18,777	Since it is sitting on the garage floor, drill it. Its easy. You can get everything you need in a kit with instuctions from http://www.glass-holes.com __________________ - Scott

04/28/2009, 09:01 AM	#4
Jackie Blue Registered Member Join Date: Feb 2009 Location: Elgin, IL Posts: 333	Ok it's going to get drilled, now all I have to do is figure out where to put the box and return or returns. __________________ How am I doing? Well I got ten fingers and toes. Current Tank Info: 120 Gallon. Custom made refugium sump 30 gallons.

04/28/2009, 09:03 AM	#5
Uncle Salty 05 Registered Member Join Date: Dec 2004 Location: South Florida Posts: 3,799	I like these personally. http://www.marinedepot.com/ps_Aquari...boxes_cpr.html They cost more but are ready for an aqualifter and are very quiet and never fail. __________________ In all that I endure, of one thing I am sure. Knowledge and reason, change like the season. A jester's promenade. - Kerry Livgren Current Tank Info: 180 gal reef tank with dual attached refugiums 20 long and 10 gallon. Plus 55 gallon True Percula breeding tank.

04/28/2009, 11:06 AM	#6
THE ROOK Registered Member Join Date: Jun 2008 Location: Springfield, MA Posts: 2,100	I believe there is an install video on glass-holes website. They're kit is pretty popular & I'd buy one in a second if needed.

04/28/2009, 11:26 AM	#7
Jackie Blue Registered Member Join Date: Feb 2009 Location: Elgin, IL Posts: 333	That second has come and gone, I have the 1500 gph one that should show up thursday, thanks everybody this whole bit would of been much more unpleasant without you guys. __________________ How am I doing? Well I got ten fingers and toes. Current Tank Info: 120 Gallon. Custom made refugium sump 30 gallons.

04/28/2009, 01:38 PM	#8
sjm817 On Yer left! Join Date: Sep 2004 Location: Northern VA Posts: 18,777	You made a good choice. Good luck with the new setup. __________________ - Scott

04/28/2009, 03:11 PM	#10
MatthewLaw Registered Member Join Date: Jan 2009 Location: East Coast US Posts: 1,564	i am using two Eshopps 800s on my 50g and 60g tanks. both overflows work excellently and no issues!

04/29/2009, 06:43 AM	#12
sjm817 On Yer left! Join Date: Sep 2004 Location: Northern VA Posts: 18,777	A U Tube will never accumulate air if the overflow is designed properly and adequate flow moves through it. If will run indefinitely without failure. You will not eventually lose siphon. People have used them for many years on end without an issue. A CPR on the other hand ALWAYS accumulates air and must use an external pump to remove it. A failed pump is just one of several failure scenarios. A clogged air nipple is another very common one. The Lifereef U Tube overflows have a reputation for being incredibly reliable. The CPRs have a reputation for high failure. They both earned the respective reputations from user experience. __________________ - Scott

04/29/2009, 06:54 AM	#13
Uncle Salty 05 Registered Member Join Date: Dec 2004 Location: South Florida Posts: 3,799	Well I must just be incredibly lucky on the CPR's and incredibly unlucky with the U tubes because my CPR has been running for over 10 years without a single failure and my tank with a U tube has to have the siphon re-started about every week or two. Believe half of what you see and none of what you "hear". __________________ In all that I endure, of one thing I am sure. Knowledge and reason, change like the season. A jester's promenade. - Kerry Livgren Current Tank Info: 180 gal reef tank with dual attached refugiums 20 long and 10 gallon. Plus 55 gallon True Percula breeding tank.

04/29/2009, 07:38 AM	#14
sjm817 On Yer left! Join Date: Sep 2004 Location: Northern VA Posts: 18,777	You have been very lucky with your CPR. Glad to see it has worked for you. Many are not so fortunate. Your U tube is either a poor unit or has inadequate flow thought it. My CPR failed twice in 3 months. My Lifreef was flawless in the 2 years I ran it and would have stayed that way If I still ran it. Use experience and opinion will obviously vary. Design principles and the physics of a siphon do not. __________________ - Scott

04/29/2009, 07:55 AM	#16
sjm817 On Yer left! Join Date: Sep 2004 Location: Northern VA Posts: 18,777	The failure both times was a clog in the air nipple in the inside of the box. This is a very common failure scenario. __________________ - Scott

04/29/2009, 08:10 AM	#17
Aquarist007 Registered Member Join Date: Apr 2007 Location: Hamilton, Canada Posts: 28,240 Blog Entries: 1	Make your own overflow---I did for 30 bucks: the price of an hob filter body replacement and a 3/4 inch u tube. __________________ I prefer my substrates stirred but not shaken Current Tank Info: 150gal long mixed reef, 90gal sump, 60 gal refugium with 200 lbs live rock

04/29/2009, 08:16 AM	#19
sjm817 On Yer left! Join Date: Sep 2004 Location: Northern VA Posts: 18,777	And the OP already decided to drill the tank anyway. That will work too LOL. __________________ - Scott

04/29/2009, 08:25 AM	#21
sjm817 On Yer left! Join Date: Sep 2004 Location: Northern VA Posts: 18,777	Capn, its a little hard to see what your DIY design looks like. You have to be sure the U Tube is full of water when power is off. This means both ends of the U Tube must be submerged when power is off. The tank side usually takes care of itself. The drain side will need a baffle or a standpipe to keep the end submerged. __________________ - Scott

04/29/2009, 09:09 AM	#23
DarG Registered Member Join Date: Dec 2006 Posts: 5,515	Overflows all continue to drain the tank until the water level in the tank gets below the edge or teeth of the internal box. Since I am not a scientist, the best I can describe a properly designed U-tube overflow and why it doesnt lose siphon when pump is shut down is due to equilibrium. Proper design between the height of the drain pipes in the outer box and/or the U-tubes in the outer box being contained in their own chamber ... so that water stops draining down to the sump BEFORE the water level in the inner and outer boxes fall to a level below the ends of the U-tubes. Again, I dont know the scientific terms or laws of physics that govern this and I dont pretend to. Obviously there is a siphon through the utubes between the inner and outer boxes. But it has something to do with gravity and equilibrium so that the siphon stops draining water between the inner and outer boxes yet the water remains in the U-tubes ... I assume because the pressure is equalized in the tubes at a certain point BEFORE the water level drops below the ends of the U-Tubes because of an equalization of the water levels/pressures between the inner and outer boxes. The key seems to be the U-tubes being in their own chamber in the outer box ... and/or the drain pipes to the tank being above the level of the bottom of the U-Tubes. The Lifereef has the central chamber in the outer box that the U-tubes empty into. And so do the other designs that most people seem to recommend as reliable. Sorry, I dont know the science. But if the outer box is non chambered which just allows the U-tubes to empty into the open area and the tops of the drains are below the bottoms of the U-tubes then the siphon will continue until the Utubes empty and then obviously they wont resume siphon when power is turned back on. And I dont know if it goes beyond just that and the U-Tubes actually require their own chamber in the external box. Again, I think that all the overflows that seem to be recommended all have this dedicated chamber for the U-tubes to empty into in the external box. And I realize that this probably doesnt help you at all because I dont know the technical side of it in order to explain it. Which is probably why I just bought the Lifereef instead of any of the other recommended, less expensive U-tubes based on it having the absolute best reputation of all the external overflows ... this of course after learning a valuable lesson after having an aqualifter pump fail on a CPR overflow and realizing that Murphys law is bad enough without tempting it by hoping I would have better luck with a second aqualifter (and on top of that, also hoping the air fitting wouldnt clog on the CPR). Im sure one of the more scientific minds could explain it better.

04/29/2009, 09:13 AM	#24
MatthewLaw Registered Member Join Date: Jan 2009 Location: East Coast US Posts: 1,564	i think that is a pretty accurate description. at least it makes sense and applies when I shut off my return pump to similate a failure to ensure that everything is properly set up.