The Lifereef is a u-tube style overflow that doesn't require a separate pump to maintain a siphon unlike the CPR. It's a malfunctioning pump that cause most CPR failures.

There are other u-tube overflows out there like Hurricane, but the materials and workmanship of the Lifereef put it a cut above the rest. The Lifereef is also big enough to accomodate a Stockman-style silencer whereas the cheaper versions are too small and possible too flimsy to do so.

I used one for several years before getting a drilled tank and it never once failed.

Statements like that lead to the common misconception that the CPR overflows REQUIRE that pump in order to restart after power failure. They should NOT require any kind of pump to restart after power failure. They are just like every other good siphon in that they have water collection boxes on either side of the siphon to ensure it restarts properly. Without those boxes, no siphon restarts automatically.

The pumps are there as a backup to ensure the siphon never collects air in the siphon. It is a fair statement to say that the rectangular shape of the CPR siphons may create a situation where more air might collect in the siphon, but I believe that all siphons have the potential to collect air bubbles that could cause siphon failure at any time..not only on restart.

It would not matter what kind of siphon I was operating, I would want some sort of pump pulling air out of the top of the siphon at all times. It is just safer.

I ran a CPR siphon for about 6 years. I used a RIO600 RVT for air removal and the system was very reliable. The only maintenance I did was to periodically ensure that the air line wasn't clogged.

If you ever drain the siphon collection boxes, then starting the siphon is a lot easier with some sort of pump helping you out. Otherwise, you have to stick a flexible tube up there and suck the air out manually.

The things that I did NOT like:
1) the actual siphon portion of the CPR is black so that algae won't grow in it. Yes, but I would feel better if I could see inside to know that the siphon was running properly.
2) Impossible to clean or disassemble. If anything got in there, you can't get it out. A removable "U-tube" would be much easier to deal with.
3) Siphons don't like when you jam your arm into the tank and cause rapid changes to water level. That's when floods happened to me.

I would never return to a siphon based system myself.

Sump/overflow box.
 

Buy the materials & build your own sump/overflow box do a google search there is a ton of things you will learn and save big time.


Brian :idea:

hang on overflows
 

WARNING!! I had two tanks running these overflow systems and I found that even if they didn't malfunction, the threat was always there!! I've since drilled all of my tanks NO MATTER HOW SMALL, if you have hardwood floors 10 gals on the floor is just as bad as 100. Please take my advice and drill your tank. The staff of J+L will help you with this, or the hidden reef, also glass shops will drill your tank for you and then you can build your overflow how you want it!!
GOOD LUCK!!

i use a cpr siphon overflow and its never let me down yet :) actually i use 2 of them now hahaha

ditto on the cpr, i'm using the cpr-90, 600gph i believe, on my 33 and quite satisfied so far. however i'd like to throw in that you should get the recommended aqua lifter pump for $10. it restarts the overflow in the event of a power-outage or if the breaker seizes. if i were to restart i'd drill my tank without a second thought, but these are a quite decent option-