HOB Overflow Dependable Good Flow?

<a href=showthread.php?s=&postid=10556089#post10556089 target=_blank>Originally posted</a> by t11t5
I have had a Pro-Clear HOB overflow running for 3 years now. Not a single problem. I would buy one again if needed.

Now that you say it my second one may be a Pro Clear...
 
I have a couple u-tube style that worked well for years. But looking at the boxes now I'd not use these again without replacing them. Seems both are in pretty bad shape from the UV put out by the MH over the years.

The tubes are fine, just the boxes are yellow, cracked and hazed.

SteveU
 
so what is the point in the U on the pvc style i just have about 1in of pipe under water and as long as there is water above it no problems as well as this alows it to stop so that it dont over flow the sump and if it stops and sump return keep running it is sectioned off so that no much water go in the tank so it dont over flow as for pump burning up there is always just enough water in with it to keep it from happening
 
is there a reason it is so large of a U and does it allow for suction to restart if it loses it
 
Yes the siphon is kept when the power goes out and will restart automatically. Been running mine for 3 months now and through several power outages, this thing never failed to start right back up.
 
<a href=showthread.php?s=&postid=10541103#post10541103 target=_blank>Originally posted</a> by sanosuke
I would recommend the CPR overflows. My friend have one since 2003 and works great in his opinion.

You obviously haven't used one and you would recommend it. That';s like "I hear a story from a friend's friend of my friend"

CPR overflow design is the worst design ever got invented. That is not to say that everyone will have problem with it but it's true to say that most folks will have problem with that CPR overflow design.

In contrast, some ppl might have troubles with U tube overflow design but most will agree they work just fine.
 
<a href=showthread.php?s=&postid=10549327#post10549327 target=_blank>Originally posted</a> by krowleey
im sorry but that DIY overflow with all the pvc is horrible to look at, unless you are Sanford and son. if you dont want to drill your tank, the CPR overflow works fine with the aqua lifter. i used one for years. but now i do nothing have RR tanks. and if you dont want to use a aqualifter yu can simply use a powerhead although it will spit air in your tank no and then. the real solution is drilling the tank, anything else is just a band aid.

Use powerhead to replace aqualifter? Are you alright? Obviously you haven't seen any powerhead spews water through the venturi due to coraline algae grow at the opening of powerhead nozzle. As dhnguyen said, you know nothing about HOB overflow.
 
Just had a CPR overflow my tank last weekend. Partially my fault. I upgraded my sump return pump and it created some turbulance near the surface skimmer causing air to build up and break the siphon. I'm drilling my new tank as soon as I get the glass for the overflow box. My last tank was drilled and I never would have had this problem. I have had tanl overflows or near ones with the CPR and U tube type overflows of the old days (I remember drilling the top of my U-tubes and sucking the air out every few days). Some people go forever without a problem. Some people also lft heavy things with bad form and never get hurt. To me it's just a risk not worth taking - but that's just for me. I hate mine, and I will not miss it at all once it's gone. Doesn't mean it won't work great for you though.
 
I've been running my PVC overflow since 3/06 and it's been doing a great job... I tested a lot before I trusted it..turning the return pump off then on up to 3 hours or so..I'll never buy another pre-made overflow when this thing can be had for under 5 bucks and 15 min.
 
i had a Lifereef HOB, i never once had a problem out of it, not once did it break suction (at least not without my help) the entire time it was on my tank.
 
I've owned CPR, Amiracle, Lifereef. The CPR is a terrible design. If the overflow accumulates air, and is reliant on an external powered device to evacuate the air, it is a very unreliable design. Mine failed twice in 3 months (clogged air nipple).

The Amiracle was very reliable, but did not handle much flow. A Mag5 pretty much maxes it out.

The Lifereef was awesome. It was as reliable as the sun rising and easily flowed 2x the Amiracle.

The PVC overflows are kind of ugly looking IMO, and dont have a surface skimmer, although I'm sure one could be added.
 
Here is my overflow:

overflow.jpg


I used acrylic sheet and coppied melev.

Here is all the info:

http://reefnetwork.com/jener8tionx/weblog/3.html
 
That is a CPR type overflow, and has the same design and reliability problems. It will accumulate air, and requires a vacuum pump to remove it. Keep an eye on the water level in the C Channel. If you see an air gap in there, fix it or it will soon fail.
 
The design has absolutly no flaw. Trust me on this. If power cuts out it maintains siphon for hours. If siphon is lost, A is connected to the veturi output of a power head a readily pumps out the air and restarts the siphon. If the powerhead fails, it will still keep siphon and I get very little bubbles in the top.
 
A good overflow doesn't have or need a powerhead to pull out air. There should be no need for one. A good overflow will never accumulate any air.
 
The problem with that design accumulating air is the large flow capacity. If you aren't close to that capacity it won't wash the air bubbles through like a u-tube does, u-tubes also become unreliable if you have too many for a given flow. In the past I tried "backup" tubes thinking that in case one failed the second would take over, what I found was air accumulating in both until it created flow problems or failed.

IME a single 1" u-tube at ~400gph cannot accumulate air because the flow is to high through the tube.
Additionally any good over the back should hold it's siphon indefinately during a power outage as long as both ends of the overflow are submerged.

Tim:cool:
 
Back
Top