overflow experiences...?

[vanreefer]

Hey Canreeefers,

I am in the process of addind a sump to my 77 mixed reef....
Can anyone offer their opinions about external overflows
CPR type VS U tube
Flood prevention ( big concern)
siphon maintanance tips or tricks
Thanks for your help and opinions

Dano

[danny zubot]

If you go with U-tube style drill a hole in the top and run an airline to a powerhead in your tank. (provided there is one) The constant sucktion will ensure that the siphon never breaks due to air bubbles.

I would drill the tank personally though.

[BCOrchidGuy]

I found the U tube type grew alot of algae in them, coraline algae as well. You'll end up with bubbles all the time at the top of the U which will slow down your water significantly so like Danny said, put an airline in the top and run that to a power head (like where the bubble tube add on would go. That will draw water/air out of the U tube and keep your tube from developing bubbles.

Doug

[LostMind]

I've had both, both performed about the same for me. Both went thru a power outage with no problems.

However, if you can, drill the tank. Sooo much easier

[hawk]

If you go with U-tube style drill a hole in the top and run an airline to a powerhead in your tank. (provided there is one) The constant sucktion will ensure that the siphon never breaks due to air bubbles.

I would drill the tank personally though.

The benefit of a u-tube is that your not relying on a powerhead to keep the siphon working like a Cpr does. Powerheads will definately stop working for any number of reasons. If you drill a hole at the top of the tube and the powerhead stops or the airline pops out, won't the hole act as a siphon break? then a flood will follow. Maybe I'm not following the concept.
I currently use a Lifereef u-tube, I have also used a cpr. The tubes need to be cleaned every 8 weeks or so. The problem with the Cpr, other than having to rely on the powerhead, is that it is extremely difficult to clean and it gets plugged up as quickly as the Lifereef, but the tubes in the Lifereef are easily removed, cleaned and replaced. I have never lost the siphon with the Lifereef due to power outages.

[rayyue]

i suggest u go drill your tank instead of buy the exteranl overflow, this is my experience, if i set up my tank again, i must drill

[PrairieReefer]

I also vote for drill your tank. I did this on one tank and it is the way to go.

I also have a CPR Style (which I am going to get rid of and drill the tank). It works well and I have had no floods with it. It depends on high flow rates to keep the air bubbles out. I have lower flow rates, and you have to watch it. About once a week I have to break the siphon and restart it (which is real easy) in order to keep it flowing properly. The suction from the venturi on a powerhead was not strong enough to keep it free of air bubbles. I now have a vacuum pump on it which solved the problem. Here is a link to one of these vacuum pumps.

http://www.marinedepot.com/md_viewItem.asp?idproduct=KTALP

It is also hard to clean. It is black so it doesn't grow algae to quick but when you do have to clean it, it is a pain. The siphon section is removable but you can't get a brush around the square corners of the U so you cant clean a section of it properly. In order to clean it I have to shut down my sump for mabey 6 hours, fill the U with bleach in the sink and let it soak, then blast it with a water hose to clean out the dead algae. Thankfully I only have to do it mabey once a year.

The CPR style works well and I am fairly happy with it but best of all is a drilled tank. My current and any future tanks will be drilled.