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Home » Saltwater Aquarium Supplies  » Overflow Box  » External Boxes  »  CPR CS150 Overflow Box
CPR CS150 Overflow Box

CPR CS150 Overflow Box

Average Rating 4.5 140
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CPR CS150 Overflow Box Information

Product Manuals & Documentation

  • For glass or acrylic aquariums up to 300 gal.
  • Flow rate 1600 GPH.
  • 9 3/8" wide
  • 1 1/2" bulkhead outflow
A built in overflow is the most efficient method of draining aquarium water to a filter. If your aquarium does not have built-in overflow, CPR Continuous Siphon Overflows/Prefilters are the best means for getting water from an aquarium to a filter system without expensive modifications to the tank. They quietly skim up to six times more water than units with tubes.

The advantages of CPR Continuous Siphon Overflows/Prefilters include:
  • Adjustable water level allows you to easily change the level in your tank.
  • Black top reduces algae growth.
  • Quiet operation.
Tip: We recomond the use of an Aqua Lifter pump with the CPR overflows for trouble free operation. Another alternative is to hook the bleed hose from the overflow to the air intake of a power head. This way the overflow will continue to wok if it drawes some air into it or in the event of a power failure it will restart.

CPR Diagram

Model Width A B C D E F G H I J K L
CS50 6" 6 7/8" 8" 1 1/2" 1 7/16" 3 15/16" 4 3/4" 7 1/4" 5 9/16" 4" 3 3/16" 3 1/8" 2 7/8"
CS90 7 1/4" 7 5/8" 9 1/2" 1 5/8" 1 1/2" 4 1/2" 5 1/16" 8 5/8" 5 7/8" 3 7/8" 2 1/8" 3 5/8" 3 3/4"
CS100 9 3/8" 8" 10 1/4" 1 11/16" 1 1/2" 4 11/16" 5 1/16" 9 1/4" 6" 3 7/8" 3 1/4" 3 3/4" 2 3/4"
CS102 9 3/8" 7 7/8" 10 1/4" 1 11/16" 1 1/2" 4 5/8" 5" 9 1/4" 6" 3 7/8" 3 3/8" 3 3/4" 2 3/4"
CS150 9 3/8" 9 7/8" 10" 1 15/16" 1 1/2" 5 3/4" 5 3/4" 9" 6 7/8" 4 1/2" 3 11/16"" 5 1/4" 3 3/8"
CS202 9 3/8" 9 3/4" 10" 1 15/16" 1 1/2" 6 3/8" 5 3/4" 9" 6 3/4" 4 1/2" 3 5/8" 5 1/4" 3 3/8"

Manufacturer Info

CPR Aquatic Aquarium Supplies
In Arcata, located in Northern California, the sea is a way of life. From the advanced Marine Biology department at Humboldt State University, just up the hill from CPR’s headquarters, to Humboldt Bay, about a mile west, CPR is nestled in a perfect environment to develop equipment for marine aquariums. CPR was started in a small garage in 1987 to produce biological filters for local aquarists. People who used CPR filters were impressed by the high quality and affordable prices. Word spread and the company grew. Since then, CPR has expanded to a 10,000 sq. ft. production facility and has developed many innovative products over the years. CPR is incorporating new ideas and technologies all the time. Their goal is to allow aquarists to place the highest performing products in their tanks at reasonable prices.

CPR CS150 Overflow Box Reviews

Average Rating
(140 reviews)
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of 14

Definitely recommend it....

Reviewers Rating Excellent!

Posted: 5/18/2015 from HAZLET, NJ UNITED STATES
5.0 5
Experience Level: Expert

Comments: I've have this over flow box running now for 3 years with no problems. One great tip is that I use floss in the box to filter and quite the suction of the water noise. I change it as needed but also keep my return set high below the water line so when my main pump goes off my refugium doesn't over flow... Great quality and would recommend..

1 of 1 People found this review helpful, did you? Yes No

Excellet flow

Reviewers Rating Great

Posted: 5/15/2015 from CLEARWATER, FL UNITED STATES
4.0 5
Experience Level: Intermediate

Comments: This overflow is excellent. The flow is high and works smoothly and quietly. The only difficulty is when the suction line connected to the pump gets plugged with a piece of goo, algae, etc. - when that happens the tank overflows the rim onto the floor. It is absolutely necessary to do regular maintenance to make sure that the suction line does not clog.

1 of 1 People found this review helpful, did you? Yes No


Reviewers Rating

Posted: 2/28/2015 from HONOLULU, HI UNITED STATES
0.0 5
Experience Level: Intermediate

Comments: I have three of these, and I hate the beginning this works perfectly fine, but as time goes on and solid wastes starts to build up inside of that filter, it tends to block it off slowly. In the end what happens is that the water doesn't flow out as quickly and then over flows in the, the pump becomes clogged as well. -MARINE DEPOT STAFF: PROPER ROUTINE MAINTENANCE WILL INSURE THAT THIS ITEM WORKS IN PROPER AND EFFICIENT ORDER FOR MANY YEARS WITHOUT ISSUES.

1 of 1 People found this review helpful, did you? Yes No

CPO overflow

Reviewers Rating Excellent!

Posted: 9/23/2014 from CUYAHOGA FALLS, OH UNITED STAT
5.0 5
Experience Level: Intermediate

Comments: This is a very high quality overflow that is easily the best on the market. Works as advertised and is quiet.

4 of 4 People found this review helpful, did you? Yes No


Reviewers Rating Excellent!

Posted: 8/23/2014 from STEENS, MS UNITED STATES
5.0 5
Experience Level: Intermediate

Comments: I have been using a 1200 model on a 75 gallon reef tank for over 13 years and have never had a problem with it. Also I have never had to clean it. Tip take foam sleeve out of the back. I don't ever use it.

1 of 1 People found this review helpful, did you? Yes No


Reviewers Rating Average

Posted: 5/9/2014 from BLAINE, WA UNITED STATES
2.5 5
Experience Level: Intermediate

Comments: The cs50 does NOT come with ANY way of connecting the tubing to the unit. It's a nice overflow, but a headache to deal with. Won't purchase from this manufacturer again.

3 of 5 People found this review helpful, did you? Yes No

Needs a dosing pump

Reviewers Rating Great

Posted: 4/9/2014 from CONCORD, NC UNITED STATES
4.0 5
Experience Level: Intermediate

Comments: I finally installed this overflow on my system and I do like it better than the U-tube design I had previously. The only downfall is that you will need a pump to keep the air bubble from appearing in the overflow area.

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Reviewers Rating Excellent!

5.0 5
Experience Level: Intermediate

Comments: This overflow is the best you can buy! You need the aqualifter pump with it so do not try to use it without it. Hook it up turn on the pump and your moving water. I do not want to drill my tanks and this was my best option.

3 of 5 People found this review helpful, did you? Yes No

overflow box

Reviewers Rating Excellent!

Posted: 3/27/2014 from VACHERIE, LA UNITED STATES
5.0 5
Experience Level: Beginner

Comments: Love it

2 of 2 People found this review helpful, did you? Yes No


Reviewers Rating Unsatisfactory

Posted: 3/26/2014 from North Wilkesboro, NC UNITED ST
0.5 5
Experience Level: Expert

Comments: I hate this box and the tom's aqua lift. I will never buy another one that doesn't have U tubes in it. Put this CPR overflow box with toms aqua lift on my 125 gallon reef tank. When I set my two mp40's on in wave mode the movement of the water is to much for this style box. It's always getting air in it and stops the overflow. I took a double U tube box off a tank I'm not using tonight and now I can run my mp40s wide open without lose of suction. I give the CPR overflow box and toms aqua lift the worst two thumbs down I can. Don't buy either of these if you plan on upgrading to a wavemaker. Bty even without the wavemaker you still can't trust the toms aqua lift to not stop working while your away from home, so beware that you might come home to a wet floor one day.

3 of 10 People found this review helpful, did you? Yes No

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