How to quiet a CPR BakPak

[spdntckt]

I am just now setting up a used CPR MRT that I got from a friend. For those who aren't familiar, this is basically a 11G (or somewhere around there) nano with a built in CPR bakpak on the rear. I'm not sure if it is normal, but the pump that runs it is pretty noisy. Does anyone know if there are replacements that run more quietly? (either RIO or other?). I've never used pumps that small before, but this sucker is much loader than the 700 Mag on my full size reef.

Thanks for inputs!

 

[reefhound]

Scott it sounds to me that the rio pump is going bad. try a maxi jet. i still run mine with the rio 600 ( yes i know i should trash it) but it is working well and can not here it over the mag 5 return on the 55 its on right now. most people do not like rio's and i to have had a 2500 trash one of my system's but the small one's do seem to work.

 

[Anonymous]

I added a needle valve to new tubing and it was quiet after the fact. But before trashing it I would break it down and give it a thorough cleaning. It may be dirty or it may be assembled incorrectly. The smaller rios do not seem to have the problems associated with the larger 1700s and up.

 

[rBeOeBf]

Is the pump itself noisy, or is it just the air being sucked in? I've got a bak pak with the original rio, and if I block the air intake, the pump itself runs silent. It's only the air being taken in that causes any noise. If the pump itself is making noise, sounds like there's a problem.

Bob

 

[spdntckt]

Thanks for the input guys.. After your suggestions I ran a few experiments..

Took the RIO and held it under h20 in the aquarium with the intake hose under water so it couldn't suck air.. Ran quiet.

Put the RIO back into the skimmer, plugged up the intake.. ran quiet.

Took the muffler off the intake hose, ran real loud, but a different kind of noise - more of a sucking noise (i've never owned a venturi type skimmer before - so this noise was new)

With the muffler on the intake I dont hear an air sucking noise - what I hear is more like a constant humm - a humm that is much louder than the pump makes when it is run with just water through it. I am wondering if - somehow - the RVT system just makes it louder with all that turbulence of air/water going through it? Next test will be to try it with just a straight venturi and no RVT...

Another thought is that there is enough wear on the internal bearings of the pump that the extra turbulence causes more vibration. I have no idea how old this pump is as i bought it used.

Keep tuned.. Thanks!!

 

[Anonymous]

Try adding a check valve. It will lower that sucking noise considerabaly.

 

[Rich-n-poor]

I get the same hum from mine when a snail gets between it and the back wall of the tank. It could be the pump is actually making contact with sometthing. perhaps you could insert a piece of sponge between it and the back wall of the tank.
this will catch dirt but a small piece shouldnt really act as a nitrate trap.
HTH

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Ferrari F355