Mon-Thurs 7am-5pm PST
Fri 7am-4pm PST

Questions about products, orders, shipping?
Contact us by call or email

Marine Depot KleanWater 4-Stage Advanced RO/DI System - 100 GPD


Item #: MD9115

Ships Free!

Temporarily Out of Stock

We have assembled a high quality yet economical water purifying system that turns ordinary tap water into ultra-pure, zero-TDS, water for your aquarium. Harmful impurities such as nitrates, phosphates, silicates, pesticides, heavy metals are removed though filtration and absorption; leaving behind KleanWater as nature intended!

4-Stage KleanWater Advanced RO/DI System Features:
  • High Silicate Rejection TFC Membrane - 100 GPD
  • 1-Micron Sediment Filter
  • High-Capacity Carbon Block Cartridge with chloramine-removal capabilities
  • Nuclear-Grade Mix-Bed DI Resin Cartridge
  • Pressure Gauge to Monitor Pre-Filter Performance
  • TDS Monitor to Measure System Performance
  • Manual Flush Valve Kit to extend TFC Membrane Life
  • Heavy-Duty Aluminum Mounting Bracket
  • Quick Connect Fittings
  • Made in the USA!
  • One-year warranty
  • Garden Hose Adapter
  • Filter Wrench for filter removal
  • 6’ of tubing for inlet and outlets
  • Instruction Manual
Note: A flush valve can significantly enhance the life of TFC membrane by flushing out any harmful impurity from the membrane.

Manufacturer information

Marine Depot was started in 1998 by a self-professed reef geek and pre-med student Ken Wong. Ken envisioned a one-stop shop where customers could find everything they needed, from technical product specifications, reef aquarium information, expert advice on the hobby and friendly one-on-one customer support. Having grown from a one-man crew to being one of the world’s largest suppliers of reef and marine aquarium products, this very core philosophy still lives strong in the Marine Depot culture 20 years later.

5 Stars


Reviewed on
February 08, 2021

Yes, I would recommend this.

Great RODI system

Pros: TDS meter and pressure gauge

Works amazingly well even after several years. It's easy to set up and the TDS meter is super useful. It's easy to replace filters and everything.

Was this review helpful? 0 0


Reviewed on
August 08, 2020

Yes, I would recommend this.


works great easy to set up

Was this review helpful? 0 0


Reviewed on
June 16, 2020

Yes, I would recommend this.

Great Product

Pros: Easy set up and use

Cons: None so far

I needed to add a RO/DI system in order to provide water for my upcoming 100 gallon saltwater tank. This system was easy to set up and just as easy to use! I'm excited to take another step into the hobby and looking forward to the money I'll save by not having to purchase water from my LFS

Was this review helpful? 2 0


Reviewed on
June 02, 2020

Yes, I would recommend this.

Beautiful RO/DI

Pros: Simple and easy

Cons: None

You guys hit this one out of the park
Really love this unit and it works great
Has everything you need and well worth the money
255ppm coming into the unit and 0ppm coming out of the unit
And better yet Christian at marine depot gave me over the phone step by step set up information on how to install the automatic shut off system (sold separately)
People don’t waste your time and money buying stuff from any place elsewhere
I want to thank Scott and Keith and Christian and the whole staff there when they say customer service they really mean it

Was this review helpful? 1 0


Reviewed on
May 25, 2020

Yes, I would recommend this.


Pros: Great filtration. 0 problems

Cons: Nons

I can confirm the 2 to 1 for ratio. Easy to use connected to my hose with no leaks. 0 TDS coming out. My tank has been very happy that I made this purchase. Highly recommended.

Was this review helpful? 1 0


Reviewed on
May 16, 2020

Yes, I would recommend this.

Just what I needed.

Pros: Happy coral

Cons: Takes a while to produce water.

Been using regular tap for a while and since I've had this my coral look way happier. Definitely a must.

Was this review helpful? 2 0


Reviewed on
May 14, 2020

Yes, I would recommend this.


Awesome RODI by Marine Depot, received it a couple weeks ago and it is working flawlessly.

Was this review helpful? 2 0


Reviewed on
April 25, 2020

No, I would not recommend this.

Getting 440 in and 44 out

Pros: Relatively easy to connect with great video support from Marine Depot!

Cons: 440 in and 44 out may not be enough to sustain my aquarium.

I am running this RO/DI system with some fairly hard city water from Garden Grove, CA. Initially it ran at 440 in to 0 out for about 5 gallons. I recently purchased the system as my local shop closed and I need to do water changes. This system has now processed about 30 gallons of out total output. Stable at 440 in and 44 out. Hoping 44 TDI is okay for the marine aquarium. I bought an additional TDI meter and the 42-44 out is consistent on both the TDI meter on the system and the handheld TDI.

Was this review helpful? 0 1


Reviewed on
April 13, 2020

Yes, I would recommend this.

Easy to use

Pros: 0 TDS water. Easy to set up and use.

Cons: None.

This RO/DI unit is great. My water goes in 128 TDS and comes out 0 TDS. It appears to have an output close to advertised, as I get 5 gallons in about 1.5 hours. It comes pretty much set up and ready to use with easy to follow instructions to complete set up. Attached easily outside using the garden hose attachment.

Was this review helpful? 0 1


Reviewed on
April 09, 2020

Yes, I would recommend this.

Good quality

Highly recommended for reef tank

Was this review helpful? 0 0

We use cookies to provide a personalized site experience. By continuing to use & browse this site, you agree to our Privacy Policy.