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RO Systems

Aquarium RO Systems

Useful Links:
Article on RO Systems (bottom of page)
The Preparation of Water For Aquariums (bottom of page)
RO Systems: AquaticLife Classic RO Systems: AquaticLife RO Buddie & RO Junior
50 GPD. The AquaticLife Classic RO Systems economically filter water using standard 10" cartridges. The Classic RO systems provide up to 50 GPD of economically filtered reverse osmosis water, removing harmful substances such as heavy metal ions and total dissolved solids from tap water.
50 GPD & 100 GPD. The AquaticLife RO Buddie Reverse Osmosis Systems feature a small footprint that makes it easy to place under cabinets or in limited spaces. These affordable and easy to set up RO Systems use standard cartridges and the system is designed so it's easy to replace the cartridges.
RO Systems: AquaticLife Twist-In RO & RO/DI RO Systems: Coralife Pure-Flo
100 GPD. The AquaticLife Twist-In RO & RO/DI filtration systems are very compact water purification solutions. The new twist-in media cartridge design makes filter changes simple, easy and clean. No tools required and no mess. The twist-in cartridges can be easily changed in only seconds with just a quarter turn and the supply water to the unit does not have to be turned off to replace any cartridge. 2-Stage simple Water Filtration Unit also available.
24 GPD, 50 GPD & 100 GPD. The Coralife units come with a variety of options. They can be purchased with or without the deionization cartridge and in pumped or non-pumped versions.
RO Systems: Ice Cap RO Systems: SpectraPure
100 GPD. The Ice Cap Smart 4 Stage 100GPD RO/DI is like no other. It is equipped with a super quiet booster pump which allows the system to run at peak efficiency capable of providing a 2 to 1 waste to product water ratio (w/ ideal temp & pressure). This is a very eco-friendly reverse osmosis unit.
60 GPD, 90 GPD, 180 GPD, 600 GPD, 1400 GPD. SpectraPure makes everything from 60 GPD consumer units to the much larger Producer commercial units. For the absolutely cleanest water, choose the SpectraPure five-stage units. These units have two DI cartridges as well as the usual TFC membrane, sediment pre-filter and carbon pre-filter.
Float Valves RO System Additives
Float valves for topping off aquarium water
Reverse osmosis can work too well. These products re-introduce needed minerals to reverse osmosis water.
TDS Monitors Replacement Media: AquaticLife
TDS Monitors will tell you when to change your RO membrane and DI resin.
Replacement carbon, micron cartridges & TFC membranes for AquaticLife aquarium RO Systems
Replacement Media: Coralife Replacement Media: Kent Marine
Replacement carbon, GAC, 1 micron cartridges & TFC membranes for Coralife aquarium RO Systems
Replacement carbon, deionization, 1 micron cartridges & TFC membranes for Kent Marine aquarium RO Systems
Replacement Media: SpectraPure Replacement & Plumbing Parts: AquaticLife
Replacement carbon, deionization, micron cartridges & TFC membranes for SpectraPure aquarium RO Systems
Plumbing fittings, float valves and red, yellow & blue Polyethylene aquarium tubing for RO Systems
Replacement & Plumbing Parts: Coralife Replacement & Plumbing Parts: Kent Marine

Replacement & Plumbing Parts: SpectraPure

Aquarium RO System General Info

What do RO and RO/DI units do?
  • The TFC membrane removes calcium and magnesium (which make up general hardness, GH) and any carbonates (that make up the carbonate hardness, KH). This leaves you with truly soft water.
  • The Sediment pre-filter is a fine (1 or 5 micron) mechanical filter to trap large particles in the water, and some bacteria.
  • The Carbon pre-filter removes large particulate waste and chlorine in the water. This is especially important with TFC membranes, as the chlorine will degrade their performance.
  • The Deionization (DI) cartridge found in RO/DI units removes some other chemical compounds often found in the water--primarily nitrates, phosphates and silicates.
How do RO Systems work?
The RO TFC membrane operates as a semi-permeable membrane that is placed under pressure (from the water supply) to cause water to pass through the membrane in a Reverse Osmosis direction, producing pure, soft water.

What are the RO System maintenance costs?
The sediment pre-filter, the carbon cartridges and the Deionization (DI) cartridge will need to be replaced after about 6 months or approximately 1000 gallons of RO water produced, depending on local water conditions. The RO membrane should be good for approximately 3 years.

What types of aquariums should use RO water?
All aquariums should use RO water because tap water contains many impurities. These impurities include phosphate and nitrates, which fuel algae growth. Copper--highly toxic to invertebrates--can be leached from household pipes.

What needs to be added to RO water?
Because an RO system will remove almost everything from the water, you will need to add back in some essential minerals. Marine aquarium salt mixes all contain these essential minerals. For freshwater use, you need to add back electrolytes, as the RO water will be too pure for the fish or plants. You will also need to add some type of buffer to prevent wild fluctuations in the pH value.

We often are asked about the preparation of water added to aquariums. Here is a quick primer.

The Preparation of Water For Aquariums

The water you add to your aquarium needs to be pure. Very pure. Pure water has the following parameters:
  • Ammonia = 0.0
  • Nitrite = 0.0
  • Nitrate = 0.0
  • Phosphate = 0.0

RO or RO/DI Water
  • Ideally, you will use RO or RO/DI water. We carry several RO & RO/DI Systems from Coralife, AquaticLife and SpectraPure. For a reef aquarium get a RO/DI unit.
  • RO or RO/DI water can also be purchased from local fish stores, “Water and Ice” type stores, as well as coin operated machines in front of the grocery store.
Tap Water
  • Although not ideal, many people use tap water for their aquariums. Just remember, tap water has either chlorine or chloramines. Chlorine will air out if you leave you replacement water in a bucket, but chloramines will NOT air out. Tap water could also have phosphates, and heavy metals.
  • If you’re using tap water, it needs to be treated. Brightwell Aquatics Erase-CL Water Conditioner, Seachem Safe, Kordon Amquel and Continuum Aquatics Fraction are all great products for treating your water.


Water for Top Off
  • RO Systems will remove most of the minerals in your water. If you’re just replenishing water lost to evaporation then untreated RO or RO/DI water is perfect (as the minerals do not evaporate).
Saltwater for Filling a Tank or Water Changes
  • Most salt mixes used for filling tanks or for water changes are formulated for RO and RO/DI water. You may want to test your freshly mixed salt water and add buffer and calcium as needed before adding to the tank.
Freshwater for Filling a Tank or Water Changes
Test Your RO Water
  • Test your RO water periodically with a TDS Meter. This will give you an added level in confidence in the water you’re adding to your aquarium, and let you know when it’s time to change your RO System cartridges. Some RO Systems come with a TDS. We carry a number of TDS Meters.