Matching pump and overflow

[iwishtofish]

I am setting up a 29 gal tank with a 10 gal sump. I am looking at placing an eheim 1250 pump (320 gph/ max head 6.5') with a CPR CS90 overflow rated for 600 gph. The pump will need to pump the water 3.5' back up to the display tank. Is this a good match, particularly with respect to maintaining the siphon in the overflow? I also have two seio powerheads for circulation in the display tank. Any suggestions greatly appreciated!

 

[sjm817]

There is nothing that you can do to a CPR overflow to make it maintain siphon. It cant do it on its own. The design is such that it always collects air and will lose siphon unless you use a powerhead or vacuum pump (Aqualifter) to continuously evacuate the air accumulation. Even then, it is failure prone. A U Tube overflow does not have this problem.

 

[Jim_S]

Couldn't agree more with sjm.

Go with the u-tube design. You'll save yourself some big hassles down the road

Jim

 

[JOSEPHLB]

When I start my U-tube siphon and if I occasionally get a small bubble in it, I can move the U-tube up and down furiously to force the bubbles through and it still maintains its siphon without any disruption at all. Thats how strong the siphon is once you get the flow going.

 

[iwishtofish]

I have heard that U-tubes are the way to go, but I can't find any commercial versions for sale by the main online vendors. I really don't want to make one myself. Can anyone recommend a good one, and an appropriate flow rate for my pump choice? Thanks

 

[Jim_S]

http://www.lifereef.com/siphon.html

 

[iwishtofish]

Thanks for the link jimdogg187. I will definitely check them out!

 

[sjm817]

Lifereef is the best HOB overflow that you can buy. Extremely reliable and high quality.

 

[JOSEPHLB]

If Lifereef's product is out of your price range you can go with a Hurricane Quietflo 600: http://store.hurricanefilters.com/quprov.html

Its lower quality, but it uses the same concept and design and works well.

 

[NYReef]

Lifereef is the best, I use one and love it. I had an Eheim 1250 pump as a return from my sump/refugium, but was disappointed by the flow. I went with a Mag5 and am much happier, the flow is so much better then the Eheim at the same height, about 4'.

 

[iwishtofish]

Thanks to everyone for the advice on the overflow. I think Lifereef it will be, as I live in a 3rd floor apartment and want to minimize flood risks as much as possible! As for the pump, should the pump flow always be less than the overflow capacity, or should it match the overflow rate as closely as possible? Sorry to post such newbie questions here, but even with all my thread surfing I have so far missed these answers...

 

[sjm817]

The pump rate should be less than the overflow. There should be a sufficient amount to keep the bubbles pushed through the U Tube (~ 200 GPH). I think the 1250 is a good choice for that setup.

If you are using a small pump like that, you may want to get the smaller, optional 3/4" U Tube. Talk to Jeff about it when you order the overflow.

 

[sdreefer21]

Fortunately i was home working on my reef when the power went out and my CPR overflow lost its siphon. And to be honest ever since it happened that day i was scared. The water from my sump filled my 60 gallon in no time! I had time to yank the cord to all of my electrical just before it all got drenched. Man that woulda sucked! Drill your tank or buy a better overflow. But take it from me a 200 mm/hg spike in your blood pressure at the first power outage will be enough to make you wanna throw that thing away...

 

[mg426]

Lifereef is the way to go hands down.