TDS Controller vs Mineralizer? – Difference between a TDS Controller and Mineralizer?

The prime or the main purpose of a RO water purifier is to remove even the minute of the impurities from the water making it suitably clean & pure for drinking. However, while doing so it tends to remove the salts that are dissolved in the water, primarily known as TDS. Undoubtedly, with all the harmful salts removed few essential & vital salts are important for the human body that also gets removed. Here, the concept of the TDS Controller vs Mineralizer or Modulator comes in.

Certainly, most of the RO ones comes with the feature of TDS modulator / Controller or Mineralizer in them. But, what exactly is TDS Controller vs Mineralizer or Modulator? Let us discuss this concept in brief.

What is TDS Controller?

Particularly, as the name suggests the TDS controller is a device unlike the filter cartridges or membranes, that help to control the TDS level of water. It is quite inexpensive, hardly would cost about 150 to 350 bucks or so, and compact in its size. Basically, it does not tend to purify the water.

TDS Controller in RO Purifier

Need of TDS Controller Water Purifier

Least to say, natural water contains multiple salts & minerals in it including heavy metals like lead, arsenic & fluorides. Altogether, these when dissolved in water tend to decide the level of the TDS or Total Dissolved Solids in water.

Nevertheless, as mentioned earlier, when the RO processes the incoming water through it the basic mechanism is to arrest the dissolved salts & minerals from the water. In doing so, it removes about 90% of the dissolved salts from the water. However, there are some minerals & salts such as Sodium, Calcium & Magnesium that is vital for our growth. As a result, even these get removed. All in all, the water with a 1200 ppm of TDS after passing through the RO membrane comes out as one with 120-150 ppm TDS.

If you taste this water, this would taste you mild as the pH has been dis-balanced because of the removal of all the minerals & salts. this water may be pure & clean to drink but not healthy.

Certainly, this is where the use of the TDS Controller in water purifier comes into the picture.  Basically, to bring the TDS levels of the water back to the normalcy of 300-500 ppm. It works to improve and raise the level of required minerals in the water.

How TDS Controller Works?

Altogether, the TDS Controller is a manual device that comes with 2 input ports, 1 output port & a set/control screw.  Most of the RO purifiers have TDS Controller in-built inside the entire packed assembly, so to get its access, you may need to open the cover first.

In detail, the water that comes into RO gets divided into two zones before entering the RO membrane.

One stream of water goes into RO for purification and comes out as one having very less TDS level that is inefficient for drinking.( RO with TDS Controller ) On the other hand, the other stream bypasses the RO and enters the UV panel, Activated carbon filter or Micro-filter, ultrafilter depending on the design aspect of the water purifier. Here, in this, the output water consists of the same TDS level as that of incoming water.

In particular, these two arriving water streams From RO & purified water from UV, UF, or Activated Carbon filter are allowed to meet and mix at the RO TDS Controller in a specific ratio. In short, the TDS Controller that has Control Screw in it, manually adjust the water flow to match the required ratio to control the TDS of the output water it provides.

To understand this better:

  1. If the TDS of the output water is higher, then the flow of water coming from the RO membrane needs to be raised. Simply, turn the control screw in a clockwise manner.
  2. Similarly, if the output water has TDS lower than the limit, then the water from the UV, UF, or Carbon filter needs to be raised for their flow. For this, turn the control screw in the anticlockwise potion.

As a result, the output water after the TDS Controller has effectively optimum TDS level adjusted within it for safe & healthy human consumption. So, it’s not wrong to say clear water with a low TDS level is always the best to use. Besides, since this is the entire process of controlling or to say modulating the TDS level of water you can refer TDS Controller as a TDS modulator as well.

Is it Worth Buying a RO Purifier with TDS Controller?

Undeniably, with better advantages of leveling up the TDS level, the cons of the TDS Controller is it doesn’t allow 100% passage of incoming water through it and tends to mix the RO purified water with the water purified from UF or other filters. All in all, this isn’t the most specific way to add the essential minerals as it can lead to the mixing of other heavy minerals mentioned earlier in the water as well.

Below 300 ppmExcellent for use
Between 300 to 600 ppmBetter for human use
Between 600 to 900 ppmFair & considerable
From 900 to 1200 ppmLow level of TDS
Above 1200 ppmAbrupt & unacceptable level of TDS

In short, considering that the RO catches up to 90% of TDS from the water if the TDS of water is lower than 900 ppm or close to it, then RO water purifiers with TDS Controller can prove to be a suitable option to go for. Certainly, if the water that is made available to you contains a good amount of heavy metal then RO purifier with TDS Controller won’t be a good option, except when the RO membrane in purifier is stronger than average.

Mineralizer: Alternative to TDS Controller

Undoubtedly, with the above factor in mind, new advanced technologies have been developed in the field of water purification of which Mineralizer is one.

In many aspects, RO water purifiers with Mineralizer are considered to be a more optimum option over TDS Controller.

But, what exactly is Minerailizer and how is it different from TDS Controller? Let us discuss it in detail.

Working of Mineralizer Water Purifier

As discussed earlier, the RO chamber remains incapable of differentiating between essential & non-essential minerals & salts from the water. Thus, it becomes necessary to replenish the water with the lost vital minerals back to make it healthy for human drinking.

With this disadvantage of RO membrane & added cons of TDS Controller, Mineral or also known as Mineralizer cartridge comes to rescue which effectively works on the principle of Ionization & electrolysis.

It contains a cartridge or a chamber that contains essential minerals in it through which the water is passed. A variable low voltage direct current is applied for the electrolysis process to occur in the ionization chamber.

As a result of this, anti-toxic positively charged Silver & Copper ions are released that helps to arrest bacteria & algae-like organic impurities in the water. Also, it infuses other essential minerals required in the water that is lost during RO purification. Altogether, the postive terminal of Mineralizer produces acidic water, whereas the negative terminal gives out alkaline water, this completely balances the pH of water giving it the natural perfect taste as well.

All in all, the water that gets contaminated with the normal purified water in the case of the TDS Controller is strictly avenged in the water Mineralizer filter unit. It does add up the lost minerals from the RO purified water but not the heavy toxic metals like lead or arsenic. 

Talking about its disadvantage, it is a set device so if the RO membrane drops the TDS level drastically, it won’t help to raise the TDS level if required except for just adding the vital minerals only.

Difference Between TDS Controller vs Mineralizer

1. As 100% or not all of the RO purified water passes through it and there happens a mixing of RO purified & normal filter purified water, it has a good chance of not removing or lowering the heavy metals concentration in the water1. Since all of the RO purified water passes through it, basically all the heavy metals are arrested in the RO  chamber so it doesn’t have the risk of heavy metals in the output water.
2. It gives the flexibility to adjust the TDS levels in the water either to increase or reduce it accordingly.2. It is a set device, that gives no leverage to change the TDS of water.

TDS Controller vs Mineralizer, Which one is Better?

With every aspect of working as well as the advantages and disadvantages discussed above, RO purifiers with Mineralizer have an advantageous upper hand compared to the TDS Controller.

To ease out things, in short, if the water that is made available to you has multiple heavy metal dissolve din it, it better to opt for RO purifiers with Mineralizer that have no option to adjust the TDS level but to just add the essential minerals lost during RO purification.

However, if the water at your place is free from the heavy metals and has lower TDS levels then Water purifier with TDS Controller become a suitable option.

Lastly, before selecting the one make sure about the purification strength & capacity of the RO membrane in the purifier as well.

In case, you have any doubts feel free to check the FAQ on Water Purifier or drop it in the comment box below we will address them asap.

Also Read: Which is the Best Water Purifier for Home use in India? FAQs Answered


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