CPR Overflow Noisey & Gurgling

[Reefer08]

Anyone have any experience in making a cpr overflow quieter? Mine is pretty loud and gurgles water. The only way for me to make it quiet is to slow down the rate of the return pump. Any suggestions? Thanks

[SoCalSURFrider]

Ya I have the same problem.. I have 2 of them and but I guess you just get used to listening to it... Thats what we get for now drilling our tanks :(

[121ddler]

<a href=showthread.php?s=&postid=12675510#post12675510 target=_blank>Originally posted</a> by SoCalSURFrider
Ya I have the same problem.. I have 2 of them and but I guess you just get used to listening to it... Thats what we get for now drilling our tanks :(
there are many ways to quite down a hob overflow, one way is to make a standpipe or add bioballs.

[SoCalSURFrider]

wouldnt the bioballs slow down the flow though?

[121ddler]

nope...what your trying to do is break up the water from acting like its flushing down the drain. water and air is making the gurgling noise, also make sure there are no bends in the drain tube or pipe that also might cause the problem. try adding a piece of eggcrate(light diffuser) and then adding some bioballs and maybe even adding a airline down the drain like a breather

[hrburger]

All I did was stick a 90 deg elbow into the bulk head fitting at the bottom of my CPR. Noise gone for my flow.

[Reefer08]

I dont see how a 90 degree elbow would do anything?????

The drain is 1 inch black rubber tubing. Maybe I could try an airline tubing and see if that does anything, or possibly make a bigger drain line?

[td1415]

I've had a CPR overflow for a few years and I stumbled upon a solution to your problem. When I originally set up the PVC pipe that goes to the sump, I added a ball valve by accident--I meant to put it on the pipe going from the sump pump to the display tank.

Anyway, by restricting the ball valve I can completely eliminate any sound. The risk of course is that you push the valve too far and cause the CPR box to overflow. I never make any changes unless I will be home and awake for several hours, because it can take awhile before you notice the overflow box is filling. So you have to watch for that, but once you get the valve in the right spot you can pretty much leave it.

[prime311]

I don't know how cpr overflows look in the back, but I use a stockman standpipe in my overflow and its quite quiet so if you have room for a 1.5 or 2 inch coupler in the back you could do that.