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Captive Purity Refractometer

CP2111

This item has been discontinued.

Captive Purity The Captive Purity Refractometer is an incredibly accurate and easy to use device that eliminates the confusion associated with inexpensive hydrometers. Just place a couple of drops of water on the prism and hold to the light. Reads in percent and specific gravity. An absolute must for the serious marine hobbyist.

The Captive Purity Refractometer is an optical device (no batteries) dual scaled 0-100% specific gravity: 1.0 to 1.070. Calibrate with distilled water. Adjustable eyepiece, carrying case, pipette and calibration screw driver included. This model is ATC (automatic temperature compensating)


Manufacturer Info

Captive Purity manufactures water filtration and water testing supplies for marine and reef aquaria. The brand is best known for their high-quality line of reverse osmosis filter systems and accessories. Captive Purity also produces refractometers for testing salinity, portable pen-sized meters for testing pH as well as replacement filter media for their RO and RO/DI filter systems.


Warranty

12 Month manufacturer warranty.

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Overall, others give this:

  • 4.6

56 Reviewers (93%) would recommend this

Overall Rating:

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5  Star
 43
4  Star
 9
3  Star
 0
2  Star
 1
1  Star
 3
 
5
5.0
Refract

REVIEW
Great product. It's my first refractometer, and the light makes it really easy to read.
  • 1
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5
5.0
Great Product!

REVIEW
Great product, easy to use and operate. I bought this because I have a 5 gallon nano aquarium(and a 75 gallon)and checking the salinity with a traditional swing arm Hydrometer was a ROYAL PAIN! Plus I didn't really trust the readings I was getting in the Hydrometer because you never know if you have...Read More
  • 1
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5
5.0
Great refractometer

REVIEW
Great tool and is a must have. The light works great. Very accurate and easy to use. Thanks Marine Depot!
  • 1
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1
1.0
Poor Quality

REVIEW
I just got this. My old refractometer was much, much more solidly built (and cost more, $159, about ten or twelve years ago when I got it) but eventually got corroded out of useability due to saltwater drips over the years.I bought the one with the built-in light. That is where the primary defect ...Read More
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1
1.0
Unreliable

REVIEW
Very unreliable, I have had to calibrate it every time when I use it. >"<
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4
4.0
Does a Great Job!!!

REVIEW
This refractometer is very accurate and works great but the light is not very bright and is only really useful if you�re trying to read it in the dark. I would say it's a nice feature to have if you've got the money but not really worth the extra cost for a tighter budget.
  • 1
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5
5.0
An excellent device

REVIEW
It's a well built instrument that you need to have for all marine aquarists. It's easy to use. Very important that it is stored at the same temperature and the temperature of the room when you do the initial calibration has to be the same with the temperature when you do your measurement. My Instant...Read More
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Overall, others give this:

  • 4.6

56 Reviewers (93%) would recommend this

Overall Rating:

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5  Star
 43
4  Star
 9
3  Star
 0
2  Star
 1
1  Star
 3
 

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