CPR CS100 Overflow Box

$159.95 $139.99 Save: $19.96 (12%)

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This item is in stock in our East and West Coast warehouses



CPR Feature(s):
  • For glass or acrylic aquariums up to 175 gal.
  • Flow rate 800 GPH.
  • 9 3/8" wide
  • 1" 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"

Product Manuals & Documentation

CPR CS100 Overflow Box

Owner's Manual available for download in Adobe PDF file format

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.

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Drain Hose
I am in the process of order an over flow for the new sump I am getting. I was wondering of this item comes with a drain hose or does it need to be purchased separately?
Asked : Feb 09, 2017
By : David, Tennessee
The drain hose needs to be purchased separately.
Answered : Feb 09, 2017
By : MD Tech

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