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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.
Specifications
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.
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9 Questions
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Q
Will this work for a 75gallon aquarium?
Will it work on a 75gallon aquarium
The manufacturer recommends this model for aquariums up to 60 gallons. You may find that the max flow rate of 300gph it can handle is just not enough for your size tank. The CPR CS90 is a better choice for a 75 gallon aquarium. https://www.marinedepot.com/CPR_CS90_Overflow_Box_External_Overflow_Boxes_for_Aquariums-CPR-CR1513-FIOFEB-vi.html
PROS
Noise dampening features, low required parts design, siphon break recovery feature via external pump, easy to setup
CONS
Noisy, Dependency on external pump reliability for restarts.
REVIEW
I've never tried an overflow box before. This is a difficult review to write because I have come to understand the inherent challenges this solution presents as a product class as a whole. If you can't drill your tank or don't want to buy a reef ready one, then I think you are left with little choi...Read More
I've never tried an overflow box before. This is a difficult review to write because I have come to understand the inherent challenges this solution presents as a product class as a whole. If you can't drill your tank or don't want to buy a reef ready one, then I think you are left with little choice if you want to use a sump instead of a canister. Here are some of the issues and how CPR has worked to reduce/resolve them: Noisy... Water running down a tube outside your tank is going to make a decent amount of noise. Not for use in a quiet space, I can hear water running even over the TV at decent volume. This unit has an adjustable air inlet/outlet above the bulkhead that allows you to eliminate "gurgling" - it works well. The siphon control with an added water pump helps avoid siphon breakage, and sometimes restarts after simulated power outages. Out of five tests, mine restarted the siphon 3 out of 5 times without intervention. Not the best odds if you ask me. To CPR's credit they are very upfront about this solution and state that if you can drill or purchase a drilled tank - they strongly recommend it. If you do purchase, inspect VERY CAREFULLY for cracks or damage and don't use it if it has any. Install it carefully, while sturdy - its acrylic and can crack. Any cracks or damage may allow additional air into the unit which can negate the water pumps ability to restart or hold a siphon. I do like that the CPR product uses minimal parts and install was a snap. Bulkhead connects are sturdy and haven't leaked a drop by just hand tightening it. If an overflow box is the only option, then i do believe this line is the one you should purchase.Hide
If you're looking for quiet operation, keep looking. The overflow box itself is quiet but the gurgling coming from the bulkhead to the fuge in the bottom is loud. I bought the CPR recommended connection tube and there is still no relief from the gurgling sounds. No amount of adjusting the tube going...Read More
If you're looking for quiet operation, keep looking. The overflow box itself is quiet but the gurgling coming from the bulkhead to the fuge in the bottom is loud. I bought the CPR recommended connection tube and there is still no relief from the gurgling sounds. No amount of adjusting the tube going into the bulkhead relieves the noise.Hide
I was scared of putting the drill to my brand new expensive 150 gallon tank. It was too big to lug to a shop to get drilled. This was the answer. Get an aqua lifter pump with this thing and you will never look back. The pre filters work great, you can drop some chemipure in the overflow... It's just...Read More
I was scared of putting the drill to my brand new expensive 150 gallon tank. It was too big to lug to a shop to get drilled. This was the answer. Get an aqua lifter pump with this thing and you will never look back. The pre filters work great, you can drop some chemipure in the overflow... It's just a great product. Highly recommended if you are scared of drilling into your super thick shiney you new glass aquarium.Hide
I've had this for almost a month now and it's been working fine. I'm happy with its performance. If you don't want to drill a hole on your DT, this would do the job just fine. I do recommend this product.
Product is well made and does as advertised. I may have missed the opportunity to order the deluxe kit (with lid, pump, etc). Didn't see that option so I made my own.
I hade this product for 3 weeks is great low noice level easy to use....
No more having to getting water in your mouth all you need is an aqua lifter and your ready to go...
The only thing i dont like is having one more item plug into my outlets. Wish i did not have to have that aqua lifter ...Read More
I hade this product for 3 weeks is great low noice level easy to use....
No more having to getting water in your mouth all you need is an aqua lifter and your ready to go...
The only thing i dont like is having one more item plug into my outlets. Wish i did not have to have that aqua lifter pug all the time. I will try a valve to try and keep air out of the box and take the aqua lifter out and just use it when i need it...Hide
Most orders under $39 ship for only $5.99 using a mix of economy shipping methods including UPS Ground, USPS First Class, and/or SurePost. Your order will be delivered in up to 7 business days after it ships out.
free shipping for orders $39+
We ship 99% of the products we carry for free within the contiguous United States using a mix of economy methods including USPS First Class Mail, SurePost and UPS Ground. Your order will arrive in up to 7 business days. Just spend $39 or more!
free faster shipping for orders $250+
Over 90% of shoppers receive their orders within 1-2 business days. Upgrade from free economy shipping to faster shipping for only $5.99—or spend $250 and we'll upgrade you automatically!
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live plants, live foods, and frozen foods delivered to your door
We ship live plants, live foods, and frozen foods within the contiguous United States. Each of these categories is subject to its own $19.99 flat-rate shipping fee to cover the special packaging and/or expedited shipping costs required to ensure safe delivery. Orders with 12+ live plants ship free!
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A small segment of the 180+ brands we carry require that customers contact them directly if/when problems arise. You can view the full list of those brands and get their contact info here.
We are unable to accept returns of Digital Aquatics, Neptune Systems, Vertex Aquaristik, Aqua Illumination (AI), EcoTech Marine, GHL, or Seneye products once the manufacturer's packaging seals have been broken.
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