Expert RODI Advice


The Best RODI systems - Expert help and support.

Coral keepers are very demanding and require reliable and specialized RO or RODI units that have been specifically designed to fit their needs. To best serve your needs, our RO experts offer several models with varying features. The TYPHOON model is our most popular reefkeeping RODI unit. We have now built & sold over 10,000 Typhoon units through November 2022 and every one is still under our lifetime replacement parts warranty.

All of the Typhoon units are all equipped with ASOV for automatic top off. (We introduced the ASOV to reefkeeping in 2001). Every RODI unit comes pre-assembled with filters and membrane installed. Your unit is pressure tested with 70 psi. The filters and membrane are installed the day we ship. You only need to make three plumbing connections and you are done. Just connect and enjoy zero TDS water, zip, zero, zilch, nada. NO TDS.

All of our Typhoon machines are equipped with refillable DI cartridges. The Typhoon is a 5 stage RODI (Reverse Osmosis/De-Ionizing) reefkeeper is supplied with a 75 GPD FilmTec (TFC) membrane for truly great water quality and production rates.

Every Typhoon unit comes fully assembled and is equipped with all first class installation hardware, including a sturdy extruded clamp style water supply valve, drain saddle, 2) in-line ball valves, and 24 feet of 1/4" tubing. We even include the filter wrench. All fittings are push-in fittings, eliminating the need for tools, teflon tape, or glue. Comes with a fast flush flow restrictor to reduce TDS creep and prolong the life of the membrane.

5 Filtration Stages for the Basic Typhoon Unit:

  • Stage 1 - Heavy duty, standard industry size 10 micron Poly Pro Sediment filter.
  • Stage 2 - 5 micron acid washed Gem coconut carbon block filter, removing 98-99% of chlorine
  • Stage 3 - 1 micron acid washed* Gem coconut carbon block filter, that removes any remaining chemicals and chlorine.
  • Stage 4 - 75 GPD FilmTec membrane removing up to 99% of TDS (Total Dissolved Solids)
  • Stage 5 - A full sized, high capacity, refillable DI cartridge* to bring the TDS down to ZERO.

*This vertical color changing resin in the DI cartridge removes the remaining TDS missed by the FilmTec membrane. As the resin is used, the color changes. Once the color change is complete you simply install a new cartridge or buy our bulk resin and refill it. This deionization nuclear grade resin is a mixed bed DI of premium grade Anion & Cation resins.

Basic Differences Between our 9 RODI Units:

  • The Typhoon is a 5 stage 75 GPD RODI that has everything you need to make RODI water.
  • The Typhoon III is a 5 stage 100 GPD RODI that comes with a higher volume membrane, plus a DI bypass assembly, plus a RO only valve, plus a hand-held TDS Meter
  • The Typhoon III Extreme is a 5 stage 150 GPD RODI that has all features above plus a built-in pressure gauge, a built-in TDS alarm, a dual in-line TDS meter, a 150 GPD membrane, an upgraded catalytic carbon pre-filter, a tubing cutter and a float valve
  • The Compact RODI is a 5 stage 75 GPD RODI that has the same three prefilters as the Typhoon but has an inline DI filter attached to the top of the unit. The Inline DI only has 1/2 of the DI resin as the Typhoon's DI filter does.
  • The Compact III is a 5 stage 100 GPD RODI that is the basic Compact plus adds a DI bypass assembly, an RO only valve, and comes with a HM Digital hand-held TDS Meter
  • The Mighty Mite RODI is a small 4 stage 50 GPD RODI for the low volume user. No bell & whistles. Comes with two inline prefilters, membrane and inline DI.
  • The Neptune 200 GPG RODI is a 8 stage 200 GPD RODI Unit that has 3 prefilters like the Typhoon and has two membranes followed by 3 DI filters.
  • The Dual Home Reef is the Compact 50 GPD RODI plus adds a final taste filter, a pressure tank and faucet to deliver drinking water to your sink.
  • The Hurricane is a 75 GPD Dual Home Reef RODI that adds a Permeate pump to increase water pressure in the pressure tank and reduces the waste water. Plus this unit has upgraded Catalytic carbon filters, an inline TDS Meter and a vertical DI


  • ASOV Automatic Shut Off Valve. A hydraulic valve that is connected to the system and automatically stops the flow of feed water when the system is closed. Add a float valve and you make water automatically.
  • Stages. The number of filters that make up the total system. To truly understand which mircon rating to use where, please visit the Filter ArrayRecommendation page for more information.
  • GPD (gallons per day ). The GPD membrane rating is based on a water temperature of 77 degrees and water pressure of 65 PSI. RO membranes remove 90% to 99% of the feed water TDS.
  • DI or Deionization. This final stage is for reducing the membrane output TDS (Total Dissolved Solids) to zero.
  • Clear Filter Housings. Allow you to see your filters.
  • PSI Gauge. Is connected inline to measure line pressure.
  • Fast Flush. Mechanism connected to the waste water line of the system which allows flushing of the membrane to prolong its life.This flushing removes the stale water in the unit to eliminate TDS creep.
  • DI Bypass Valve. Allows you to bypass the DI stage. Useful when installing and flushing new filters. Useful for extending the life of the DI cartridge.
  • RO Only Valve. Allows you to get water out of unit after the membrane but before the DI filter. All dual home reef units have this feature.