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CPR Overflow Boxes

CPR CS Overflow Boxes 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.
CS Overflows now feature a grated inlet instead of the fish screen previously included.
Item #Description Price 
CR1511CPR CS50 Overflow Box
For glass or acrylic aquariums up to 60 gal.
Flow rate 300 gph.
6.5" wide
3/4" bulkhead outflow
CR1513CPR CS90 Overflow Box
For glass or acrylic aquariums up to 125 gal.
Flow rate 600 gph.
8" wide
1" bulkhead outflow
CR1515CPR CS100 Overflow Box
For glass or acrylic aquariums up to 175 gal.
Flow rate 800 gph.
10" wide
1" bulkhead outflow
CR1517CPR CS102 Overflow Box
For glass or acrylic aquariums up to 250 gal.
Flow rate 1200 gph.
10" wide
(2) 1" bulkhead outflow
CR1518CPR CS202 Overflow Box
Flow rate 1500 gph.
10" wide
(2) 1" bulkhead fitting
CR1519CPR CS150 Overflow Box
For glass or acrylic aquariums up to 300 gal.
Flow rate 1600 gph.
10" wide
1.5" bulkhead fitting
CR1383CPR 1-1/4 inch Drain Hose $22.49
OE1137Tom Aquatics Aqua-Lifter Dosing PumpNote: AquaLifter Pump is recommended to be used with CPR overflow boxes to draw air out from the C-Siphon$17.99
OE1140Tom Aquatics Aqua Lifter Suction Pre-Filter $4.49
CR1591CPR Overflow Sponge For CS90, 100, 102 $2.49
CR04118CPR CS Rimless Adapter for Overflow Boxes - Large $29.99
CR04119CPR CS Rimless Adapter for Overflow Boxes - Small $28.00
CPR Overflow Boxes Dimensions:
Reef Aquarium
CPR Overflow Boxes Dimensions
CS506"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"
CS907 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"2 3/4"
CS1009 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"
CS1029 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"
CS1509 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"
CS2029 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"

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