The water quality monitor measures the total dissolved solid content in your water and is a very effective way to check that your RO system is still performing optimally. will also confirm when the membrane needs to be replaced.



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By monitoring the total dissolved solids  content in the water, the user will be informed of the membrane status. Total Dissolved Solids (TDS) are the total amount of mobile charged ions, including minerals, salts or metals dissolved in a given volume of water, expressed in units of mg per unit volume of water (mg/L), also referred to as parts per million (ppm). TDS is directly related to the purity of water and the quality of water purification systems.

If the total dissolved solid content exceeds 20 ppm it is time to replace your membrane- although the raw water quality should also be considered.  In Brisbane for instance the water supply from Mt. Crosby can have a TDS value ranging from 150 to almost 600 ppm .   If you have an alkaline reverse osmosis system – the sample point should be installed before the alkaline cartridge and a non-return valve has to be installed after the sample point to prevent back flow of the alkaline water. 

Why Should You Measure the TDS Level in Your Water?

The EPA Secondary Regulations advise a maximum contamination level (MCL) of 500mg/liter (500 parts per million (ppm)) for TDS. Numerous water supplies exceed this level. When TDS levels exceed 1000mg/L it is generally considered unfit for human consumption. A high level of TDS is an indicator of potential concerns, and warrants further investigation. Most often, high levels of TDS are caused by the presence of potassium, chlorides and sodium. These ions have little or no short-term effects, but toxic ions (lead arsenic, cadmium, nitrate and others) may also be dissolved in the water.

Even the best water purification systems on the market require monitoring for TDS to ensure the filters and/or membranes are effectively removing unwanted particles and bacteria from your water.

The following are reasons why it is helpful to constantly test for TDS:

High TDS results in undesirable taste which could be salty, bitter, or metallic. It could also indicate the presence of toxic minerals. The EPA’s rescommended maximum level of TDS in water is 500mg/L (500ppm). More …
Filter performance
Test your water to make sure the reverse osmosis or other type of water filter or water purification system has a high rejection rate and know when to change your filter (or membrane) cartridges. More …
Hardness (and Water Softeners)
High TDS indicates Hard water, which causes scale buildup in pipes and valves, inhibiting performance. More …
A constant level of minerals is necessary for aquatic life. The water in an aquarium or tank should have the same levels of TDS and pH as the fish and reef’s original habitat. More …
TDS is the best measurement of the nutrient concentration in a hydroponic solution. More …
Pools and spas
TDS levels must be monitored to prevent maintenance problems.









Additional information

Weight 10 kg
Dimensions 19 × 20 × 77 cm


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