need diff. explain tube overflow box vs. cpr overflow box

[nobody]

can someone tell me the pro and cons of the CPR overflow box with the aqua lifter pump

and the pros and cons of a tube style overflow box like the eshopps

[nobody]

someone has had to use an overflow box before

[DarthOcellaris]

I wish I could help on this but I've only had one of those overflow boxes with the u-tube before.

As a matter of fact, I just put it on my temp tank about 20 minutes ago lol

[motorslave]

The CPR is not a good idea in my opinion anything that has to use a power source to keep bubbles out of it is a problem waiting to happen. A properly set up U-Tube type will work great and not have issues of building up air in the top of the tube. And, if h outer box is designed right it wont loose siphon even in a power failure, it will automatically start back up when the return pump raises the level in the tank.

[depitch]

I agree with motorslave.

There are more bad reports about CPR (Weir) Overflows than good. I use a U-tube and only had it fail once when a large cowrie blocked the tube.

HTH

Doug

[motorslave]

I never understood how CPR could market those. It needs a pump because it is a flawed design.

[Ronjunior]

From recent experience (OK, over the past year), I've had the siphon break on my dual u-tubes numerous times. The fix though was replacing my return line with double the size tubing, increasing the amount of flow considerably. Haven't had a problem since and of course this is after I remove my canopy. Wish I would have known a year ago and my Dart is more impressive now.

[motorslave]

Properly st up they work great. The velocity of water through the u-tube is key. The level in the outer box needs to be quite a bit lower than the level in the inside box, the longer drop makes a higher velocity and this prevents bubbles from building up.
But, also, like Ronjuniors experience showed, you need to have the water there to pull!

[Hop]

I ran a U-tube for many years and never had a failure. It was a lifereef. My budy had a CPR and it failed once a month. it is a flawed design and an accident waiting to happen. I would not think about running anything other than a good U-tube overlfow.

[Loverotties]

Also the CPR would be harder to keep clean.

[nobody]

i cant fit the outer box with the u tube in the back sump of the aquapod. i was going to run the u tube without the skimmer box attachment. would that be ok??????

[Fat Tony]

i don't see why it wouldn't be ok to do it that way.....unless there was a power outage and it broke siphon by the water level dropping too far...

[nobody]

the only thing i can think of if the power goes out wouldnt it drain the back sump until the bottom of the u tube was exposed. i could just cut the u tube shorter on the side that goes into the back sump of my aquapod

[Fat Tony]

hahaha... i was editing my post as you replied..LOL

[nobody]

actually i am going to drill a hole in the u tube below the water level. that way when the power goes out it will only drain to the hole then it will break siphon