Anyone using a CPR overflow with venturi pump (1 Viewer)

[tvu]

I have a external CPR overflow but am afraid of the siphon break that is caused by power loss. I have read about how some people use a venturi pump in the overflow to restore the siphon once power is up.

Does anyone have a picture of how this is hooked up? Can anyone describe how to hook this up? I've seen the crappy diagram from CPR and it doesn't give the detail I need.


Thanks,

tvu

 

[incysor]

I've only lost siphon once on my overflow due to a power outage, (or anything else for that matter), and it wouldn't have happened if I'd had the proper flow going into the tank. A piece of sponge had gotten caught in the pump and reduced the flow into the tank so the u-tube didn't stay full. That's the only time in 2.5yrs that I've had a problem. I looked around a bit to see if I could find a pic for you. I didn't find any, but I did find a few places that sell pumps, and it occurred to me that if you have a power outtage the pump isn't going to work either, so I don't really seen any advantage to having one unless you have a battery backup system that would kick in when the electricity went off as well. Really this shouldn't be an issue if things are set up correctly. I did have to periodically pull the u-tube out and wipe it out with a brush to keep bubbles from building up, which could have caused a siphon-break, if I'd let it go for a couple months.

B

 

[tvu]

The CPR overflow does not use the U-tube. I have the CS100 model. The CPR overflows break siphon on power-outage.

 

[incysor]

The CPR overflow does not use the U-tube. I have the CS100 model. The CPR overflows break siphon on power-outage.

Ah...Sorry about that...I haven't seen these overflows and just figured they were the same as all the ones I've seen. I went to their website which is totally useless, in fact I found at least one person asking for exactly the same kind of help you're needing and CPR's support tech told him to go to the LFS. I'm looking around to see if I can find a pic of one set up now.

B

 

[incysor]

Do you have a powerhead with a venturi attachment? I believe that many of the rio powerheads come with them. Maxi jet sells an attachment piece that works with their pumps. Or you could just go with the airlifter pump.

http://www.marinedepot.com/md_viewItem.asp?idproduct=AS1123
http://www.marinedepot.com/md_viewItem.asp?idproduct=KTALP

 

[Guest]

Actually I saw the overflow box Saturday when I was there -- I am pretty sure it had overflow tubes with it. They span from the inside skimmer box to the outside hand-on box.

 

[tvu]

incysor, that's a great find on the pump. The reason I asked for a picture was to see how to run the tube through the CPR overflow to get the siphon back.

The CPR does not use a U-tube. I've checked it many times and checked online(http://www.marinedepot.com/md_viewItem.asp?idproduct=CR1515) to see if mine was missing one... it doesn't use it. CPR overflows are know to break siphon as described on reefcentral.com.

I guess common sense says to snake a airline tube from the outer side of the overflow to the inside of the tank where water would be but wouldn't the powerhead/venturi attachment run dry then once power is restored and risk burning out the venturi pump?

Isn't there anyone out there actually doing this or is everyone using RR tanks?

 

[incysor]

incysor, that's a great find on the pump. The reason I asked for a picture was to see how to run the tube through the CPR overflow to get the siphon back.

The CPR does not use a U-tube. I've checked it many times and checked online(http://www.marinedepot.com/md_viewItem.asp?idproduct=CR1515) to see if mine was missing one... it doesn't use it. CPR overflows are know to break siphon as described on reefcentral.com.

I guess common sense says to snake a airline tube from the outer side of the overflow to the inside of the tank where water would be but wouldn't the powerhead/venturi attachment run dry then once power is restored and risk burning out the venturi pump?

Isn't there anyone out there actually doing this or is everyone using RR tanks?

Actually you attach the airline tube from the overflow to the venturi adapter on your powerhead, when the PH turns back on with the rest of your equipment the water it's pumping in your tank pulls the air out of your CPR and you regain siphon. The airlifter does the same thing, but it sits outside the tank. I've never seen one of these so I didn't recognize what was going on with the pics I saw of the boxes, it just seemed to be missing the u-tube in all the pics, until I investigated a bit closer.

From the comments on RC, I'd guess that many people just don't use CPR overflows. The only advantage they seem to have is that the inside box is a bit smaller, and they claim to surface skim more effectively than normal overflow boxes. However from the threads I read not too many people seem to think those benefits outweigh the possibility of losing siphon and flooding the floor. Since no one here seems to use one, or have a pic of how to attach your airline to a PH or an airlifter pump, maybe asking if anyone on RC has a pic of theirs hooked up so you can see how it's supposed to go. Another possibility would be to ask the next time you go to the LFS...Kinda like the idiotic support staff suggested on the CPR website.

Sorry I couldn't track an image down for ya.

B