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Aquarium Supplies
Home » Saltwater Aquarium Supplies  » Reverse Osmosis  » RO Water Filters  » 35 to 60 GPD  »  Captive Purity 35 GPD Compact RO
Captive Purity 35 GPD Compact RO

Captive Purity 35 GPD Compact RO

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MSRP: $123.00
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Captive Purity 35 GPD Compact RO Information

Captive Purity represents the highest quality in reverse osmosis technology. Captive Purity Reverse Osmosis Systems meet stringent standards and far exceeds the quality of systems from other manufacturers. A wide variety of options ranging from economy 2-stage units to top of the line 4-stage RO/DI units are available to suit your exact needs. Drinking water systems and custom installation solutions are available. Captive Purity Reverse Osmosis Systems are engineered and manufactured under strict guidelines to produce extremely pure water with exceptional focus on minimizing phosphates and silicates. This is a very important feature for reef aquariums.
  • Remove over 98% of all ionic impurities.
  • Remove over 95-96% of organic impurities.
  • Remove colloidal and particulate impurities.
  • Remove micro-organisms and pyrogens.
  • Remove chlorine, chloramines, pesticides, etc.
  • All systems include a non-corrosive 3/4" plastic garden hose adapter (non-brass).
2-stage Compact RO System Features:
  • Ultra-compact and economical reverse osmosis system.
  • 1500 gallon chlorine removal capacity sediment/carbon combo inline prefilter.
  • High flow and rejection TFC membrane
  • Includes non-corrosive 3/4" plastic garden hose adapter (non-brass).
  • Clear Canisters.
**Receive 15% off your replacement sediment filters, carbon filters and membranes when you purchase RO/RODI unit from us.

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.

Captive Purity 35 GPD Compact RO Reviews

Average Rating
(14 reviews)
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of 2

Compact RO

Reviewers Rating Great

4.0 5
Experience Level: Beginner

Comments: I first received the Compact RO with a broken connector elbow but customer service was great in assisting me with the problem. Other than that the system works great after I fixed a minor leak with teflon tape. I would recommend this RO system to anyone who has a smaller tank or does not need to filter large volumes of water.

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Pretty simple.

Reviewers Rating Excellent!

Posted: 11/25/2013 from ANDREWS, SC UNITED STATES
4.5 5
Experience Level: Beginner

Comments: I have to agree with everyone who does NOT have a problem putting this together. I've never had an RO filter, and I didn't even read the instructions, which I guess I should have. But I can make it simple for anyone who might be confused when they get this... 1. Hook the white line up to the sink, garden hose, whatever(I used the hose adapter from my python). 2. Black and blue lines in the drain, run water for 15 minutes. (flushes carbon dust BEFORE installing membrane) 3. Turn off the water, disconnect the short white hose between the two filters, unscrew the cap, take the membrane filter out of the wrapper and install it. The end with the small o-rings goes in first. 4. Reconnect the white line and run water for half an hour. (gets the oily crap off the membrane) 5. Start collecting water from blue line. (clean) I bought this system because my tap water pH is about 9.0 due to carbonate hardness. At first I thought it wasn't working (still tested water over 8.8) because I didn't follow the instructions and didn't flush the carbon filter or wait the half hour for the membrane to get the preservative out of it. After I read the instructions and restarted, I had a pH of 7.0 and TDS below 10. Which is close enough to perfect for me. Now I just need to figure out some plumbing for a float valve so I don't have to watch this thing take 4 hours to fill up a 5 gallon bucket, but if you're going to complain about this being slow, what do you expect, it's 35 gpd? I should note that both filters in this kit say to flush for twice as long as what the captive purity instructions state. I went with the short route, everything seems to be working fine.

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Good so far

Reviewers Rating Excellent!

Posted: 9/24/2013 from MINOT, ME UNITED STATES
5.0 5
Experience Level: Intermediate

Comments: So far it seems good, I've only been using it for a day, but it works as expected. Despite what other reviews stated when I was researching, it is quite easy to put together. We'll see how the water quality is when it comes time to test.

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Reviewers Rating Excellent!

Posted: 8/12/2013 from Greenwich, CT
5.0 5
Experience Level: Intermediate

Comments: I currently have a 30g biocube which I'm upsizing to a 60 gallon tank by the end of the year. I bought this RO unit with hopes of being able to stay on top of weekly water changes to keep the water where it should be and so far after my first change I'm really happy. I bought the unit because I don't need any more production than this makes. The unit seems a little underrated, as I left it for 6 hours and it produced 15-16 gallons.. So, definitely not 1.46gph. I waited to review the piece until the water was in my tank for over a week and so far so good. Algae grows real fast so I was waiting to see what came of it.. I use Reef Salt to bring the salinity to where I need it.

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great product and cheap

Reviewers Rating Excellent!

Posted: 8/31/2012 from HOUSTON, TX
4.5 5
Experience Level: Intermediate

Comments: I bought this product for my fish tank. I was looking for a way to lower my carbonate/alk which was about 286 on average in the tank. I had a TDS level of 160-200 out of the faucet. by adding salt/ph buffer and other additives my carbonate became too high. This product has been giving me a near zero (0) level of TDS that now gives me a carbonate/alk of 160-200 where I need it to be depending on my salinity and additives. this product is at a great price and does the job.

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reverse osmosis

Reviewers Rating Average

Posted: 7/4/2012 from PALM BEACH GARDENS, FL UNITED
3.0 5
Experience Level: Beginner

Comments: It works although it is slow. I haven't had the chance to have the filtered water tested to see how effective the unit is. The biggest problem is that it came without directions on how to put the filter in. I hope I did it correctly. Otherwise, I am satisfied with its performance.

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First time buyer

Reviewers Rating Excellent!

Posted: 3/24/2012 from MARYDEL, DE UNITED STATES
5.0 5
Experience Level: Intermediate

Comments: I recieved the unit in find shape and on time. It's performance is as advertised. The only minor complaint would be that it came with no instructions as to hook it up. As a first time user of an R.O. unit I needed to ask a friend that is familiar with them for help. Very simple if you know about them but confusing the first time. Overall, I am very pleased.

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Great R.O. unit

Reviewers Rating Excellent!

Posted: 2/10/2012 from ROSWELL, GA UNITED STATES
5.0 5
Experience Level: Intermediate

Comments: Producing what seems to be more RO water than advertised. Compact and easy to use.

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Does a good job

Reviewers Rating Great

Posted: 4/11/2011 from SAN FRANCISCO, CA UNITED STATE
4.0 5
Experience Level: Beginner

Comments: I like it because it saves me a lot of time from driving and buying water. It does what it says and I think it produces more than 35 GPD. Love it.

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Little Giant

Reviewers Rating Excellent!

Posted: 7/9/2009 from TOA ALTA, PUERTO RICO
5.0 5
Experience Level: Beginner

Comments: Excellent product,easy to use and very effective. Water tastes good and it helped make my tank look cristal clear. Your fish/corals will appreciate it.

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