Reverse osmosis deionized water system

Clover Dane

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Reverse Osmosis Deionized Water System

The RO/DI means the Reverse Osmosis Deionized water system. This system is the same as the simple Reverse osmosis system. But this system is with an additional filtration stage of DI (Deionization). The purpose of the filter is to make water down to ZERO TDS.

No doubt, the RO systems are great for the marine aquarium. But it is necessary to use an RO/DI system for making freshwater. In the marine aquarium, the evaporation lost the freshwater. Therefore, use the RO/DI system.

4-stage RO deionized water system

The 4-stage system contains four stages. The first stage contains a sediment filter. On the opposite side, the second stage contains the carbon block. The third stage is of RO membrane, and the last stage consists of deionization cartridge.

6-Stage RO deionized water system

In contrast to the 4-stage system, it contains six stages of filtration. The first stage includes the sediment filter, while the second and third stage is of the carbon block. The fourth stage is of RO membrane. In this system, there are dual deionization cartridges in the 5th and 6th stages.

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Working and lifespan of the DI Filter Cartridges

The tap water firstly passes from the first stage of the system. This stage generally connects the system with the threads of the garden hose. For this purpose, it uses a garden hose adaptor. Additionally, you can utilize an adaptor of the faucet. The faucet adaptor is for connecting the system with the household faucet. The system needs an only connection of cold water. Otherwise, the hot input water will damage the system.

Reverse Osmosis Deionized Water System

Stage 1

The first stage of the system consists of the sediment filter. This filter acts as a mechanical filter. 

It enables to catch all large particles of contaminants or debris.  The sediment filter clogs after less time of use. Thus, it needs to replace after 6 to 8 months. The more need of water daily requires more replacing of the sediment filter. Over time, the color of this filter starts to change. It becomes brownish-yellow with time.

Stage 2

The second stage contains the carbon filter. This filter consists of granulate carbon. Hence, it absorbs all organics and contaminants, including chlorine and chloramines. The 6 stage system contains two carbon cartridges. This system is suitable for the heavy usage of water that contains more chloramines. As a result, the carbon filter has a short lifespan.

The carbon filter requires changing after 6 to 8 months. The lifespan of the sediment filter and the carbon filter is the same. The changing of the carbon & sediment filter enhances the life of the membrane. So then, you should change the filter on a regular schedule.

The majority of the harmful contaminants get eliminate from the filter stages. That’s why less amount of the pollutants pass from the membrane of the system. In this way, the lifespan of the membrane increases. Besides, the RO membrane is not only a critical stage of the system but also expensive.

Stage 3

The next stage of the system is the RO membrane. It is accurate to say that this stage of the heart of the system. The membrane contains multiple layers and ensures the removal of all contaminants. For example, the contaminants include slats, bacteria, and heavy metals, etc.

You can monitor the lifespan of the membrane with the use of a TDS meter. The RO membrane requires changing between 12 to 24 months. This replacing also depends on the usage of water.

Next to the above stage, there are two water lines. These lines include waster and product water line. The wastewater line has a flow restrictor. The purpose of this flow restrictor is to regulate the flow. It is important for the accurate working of the system.

The waste line is also present at the connection of the flush valve kit. In the end, the valve kit flushes the membrane before and after every use. There is also an alternating usage of the wastewater line. It can easily connect with the chamber of drain or collection. The wastewater is with a high concentration of TDS but great for the garden, lawn, etc.

The function of the DI cartridge

The RO/DI system produces pure water. The production ratio of pure water is one gallon with the waster of three gallons. So, the system will waste the three gallons after the production of one-gallon pure water. Therefore, it is an excellent idea to consider the usage of wastewater for different purposes.

The product water is pure but not completely pure. It is the reason that this water passes through the deionization stage. In this stage, there are positive and negative resins. They are great for eliminating any leftover particles of different contaminants. After the DI stage, the water is perfect to use in the aquarium. The 6 stage system has dual DI cartridges. So then, they help to remove all contaminants indeed.

The TDS monitor is for the measuring of total dissolved solids. This monitor will tell you the exact amount of TDS. In the end, you will have a complete idea about the functioning of your system.

Upgrades to Maximize the Performance of DI System

You can maximize the performance of the system very quickly. For this motive, you have to monitor RO/DI system. You can utilize the pressure gauge and the TDS meter for monitoring the system’s function. The pressure gauge tells the water pressure that goes into the membrane.

Consequently, you will know how much pressure is present in the system. It enhances the optimal performance of it. When the pressure starts decreasing, then it’s time to change the filters of the system. The system will produce less amount of water when the water pressure is lower to 40 PSI. Lastly, you will not gain the optimal performance of the system.


The reverse osmosis deionized water system is better than all other systems. This system ensures the production of more clean water. It ensures the removal of all kinds of small and large particles.