Need help on CPR overflow

flower

flower

Well-Known Member
Okay...I swapped out my CPR lifter pump, and got a maxijet 600 with a ventura line. It is working to bring water into the overflow but it isn't draining the water fast enough for what is coming in. The CPR overflow is the CS90 for 600gph. The water is not overflowing but it sure doesn't leave too much space, it's just below the rim....Nothing is clogged...I checked.
I can turn down the Ehiem pump and make a slower return to match the slower output....but I would rather not. Can I add a larger maxijet? They have a 900 or would that be too strong? Those little hoses on the ventura don't seem to put out as much as the lifter pump.
 
S

saxman

Guest
If you turn your return pump down, it will decrease the flow out of your O/F even further, as the flow is proportional to your return volume. All the aqualifter pump is supposed to do is maintain siphon on the O/F, and should not affect the flow at all.
Did I understand the problem correctly?
 
flower

flower

Well-Known Member
Quote:
Originally Posted by saxman http:///forum/thread/387083/need-help-on-cpr-overflow#post_3403135
If you turn your return pump down, it will decrease the flow out of your O/F even further, as the flow is proportional to your return volume. All the aqualifter pump is supposed to do is maintain siphon on the O/F, and should not affect the flow at all.
Did I understand the problem correctly?
Stay with me, I'm a total dummy on stuff like this....
I know the return is sending more water than what the overflow is taking out...it isn't an emergancy but it's too close for comfort at the rim of the tank. I know the lifter is "supposed" to be just be keeping a syphon but it is in control of the little waterfall in the back which determines how fast the water is removed from the tank.
It's draining very well but the waterfall is just hardly flowing and it used to be really strong. I hate to slow down the return, isn't more better?
 
monsinour

monsinour

Active Member
What happened that you removed the lifter pump? I have had mine running for almost a year now with no problems. If the waterfall on the back is slower, then more from the return pump would be needed and not this maxijet.
 
flower

flower

Well-Known Member
Quote:
Originally Posted by Al&Burke http:///forum/thread/387083/need-help-on-cpr-overflow#post_3403148
Are you sure something isn't plugged on the back side of the CPR or the drain lines.
Not that I can tell, the water flows out real good. The overflow has a grid on the front and it is clear. The water just rises too slow in the overflow to drain out. The waterfall in the back used to flow strong and about 1/2 inch away from the acrylic back, now it just flows down the acrylic back...the lifter was doing the same thing but not as bad.
The lifter was being clogged with salt....I kept having to run new airline and I also had to run the pump next to the sink with hot water so it would run right again. Acrylic51 said he didn't like that pump for that reason, and told me to get the ventura type maxjet. It has always run just like I mentioned, never quite strong enough.
It's a very small maxijet and I purchased it because it said it was a 600 I assumed the 600 meant GPH which is what my overflow is rated. I THINK I saved the box, I could go look in the garage and see what the box says exactly....so I will go look for it now.
 
flower

flower

Well-Known Member
Okay...I got the box. It's a Marineland 600 multi use water pump and power head. It can be a power head or a circulation pump, it had two different propellers and two different fronts, one looks like a Coralife PH but I set up the other with the venturi line so I think that is Power Head mode???.
Which says Power Head mode 160 GPH...then it has another spec that says..Circulation Pump Mode 750...and another Utility mode max head height 3.5.....
 
2quills

2quills

Well-Known Member
Agree with Saxman here, the aqua lifter or powerhead that you're using doesn't do anything to control the amount of flow going through the overflow. Accept that is unless it is allowing air to build up in the overflow. If you are saying that all of a sudden the flow going through the overflow is alot slower and there is no air build up in the overflow then the issue is with the pump. It could be the pump needs to be cleaned, or it could be blockages in the return line somewhere. So if there is no air build up in the top of that overflow then I'd start looking at the pump and the return line. Check the drain lines real good too.
Edit, I might be a little confused. Are you saying that there is less flow going through the overflow and it's draining slow?
 
flower

flower

Well-Known Member
Quote:
Originally Posted by 2Quills http:///forum/thread/387083/need-help-on-cpr-overflow#post_3403201
Agree with Saxman here, the aqua lifter or powerhead that you're using doesn't do anything to control the amount of flow going through the overflow. Accept that is unless it is allowing air to build up in the overflow. If you are saying that all of a sudden the flow going through the overflow is alot slower and there is no air build up in the overflow then the issue is with the pump. It could be the pump needs to be cleaned, or it could be blockages in the return line somewhere. So if there is no air build up in the top of that overflow then I'd start looking at the pump and the return line. Check the drain lines real good too.
Edit, I might be a little confused. Are you saying that there is less flow going through the overflow and it's draining slow?
No it's draining just fine, it just isn't drawing water out and making a waterfall in the back like it did when it was new. So the size of the pump doesn't matter?....I will take it all apart tomorrow or some time soon and see what is making it go slower. Its a thin wall for water to pass down then back up and I haven't messed with it since I installed it. It is a clear box and it doesn't look like anything is blocking it.
 
S

saxman

Guest
So if I get this correctly, there's water in the O/F, and it's draining into the sump OK, but the water isn't coming from the tank into the rear compartment of the O/F?
Could there be an air leak in your "helper" pump's connection?
FWIW, this is why I don't recommend CPR's...they have inherent design flaws.
 
flower

flower

Well-Known Member
Quote:
Originally Posted by saxman http:///forum/thread/387083/need-help-on-cpr-overflow#post_3403248
So if I get this correctly, there's water in the O/F, and it's draining into the sump OK, but the water isn't coming from the tank into the rear compartment of the O/F?
Could there be an air leak in your "helper" pump's connection?
FWIW, this is why I don't recommend CPR's...they have inherent design flaws.
Well the air hose doesn't fit very tight, instead of the connector having the air hose fit over it (instead of a nub it has a well)...the pump has a black air hose that came with it, and it sits inside, the least little thing would make it come off.....could that cause an air leak?
 
S

saxman

Guest
If the connection isn't underwater, it could be leaking. Try wrapping the nub with a bit of Teflon plumbing tape to tighten up the interface between the nub and the hose.
 
2quills

2quills

Well-Known Member
Quote:
Originally Posted by Flower http:///forum/thread/387083/need-help-on-cpr-overflow#post_3403219
No it's draining just fine, it just isn't drawing water out and making a waterfall in the back like it did when it was new. So the size of the pump doesn't matter?....I will take it all apart tomorrow or some time soon and see what is making it go slower. Its a thin wall for water to pass down then back up and I haven't messed with it since I installed it. It is a clear box and it doesn't look like anything is blocking it.
Sorry I should have clarified a little better. I was actually referring to the return pump but I'm re-reading the thread. It kind of sounds as if the overflow is not priming completely. In that case a larger power head would probably be helpful. But I think you should try making your hose connections air tight as Sax had mentioned. If the hose connection on the top was completely sealed off from any air leaks then the cpr technically shouldn't need to rely on any pump to keep it going. But in an imperfect world we know this isn't always the case. The smaller power head probably doesn't have enough air pull to prime the overflow like the aqua lifter did. It's kind of like a protein skimmer...the bigger the pump the more air it's going to draw through the venturi by creating a vacuum in the hose. So that hose connection definately should be sealed and as tight as possible.
Does the power head have some type of adjustable air filter? Make sure it's open as much as possible. Actually, if there is some type of filter in there you should probably remove it and that should help in this case as well.
 
flower

flower

Well-Known Member
I got the little hose tight and it is now functioning perfectly....Thank you, thank you, thank you, everyone for all your help. Saxman you nailed it on what the problem was.
 
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