Ionized, Deionized, Soft, Hard – Decoding Water Terms

Navigating the world of tap water can be a bit baffling. Ever wondered about terms like “hard water” or “soft water”? Wondered if there’s something amiss with your tap water? We’re here to break down these terms and make your water knowledge crystal clear.


Ionization involves the separation of electrically charged particles in a solution. Achieving this requires applying either a positive or negative voltage to the solution. The resulting positive ions are termed cations, and negative ions are anions. In simple terms, ionization is when a substance has a positive charge on one side and a negative charge on the opposite.

In water purification, electricity can separate these ions, making them easier to filter out or eliminate via boiling. This process is also beneficial for managing gaseous substances like air or emissions from combustion engines.


Deionization is the art of extracting dissolved ions from a solution. This method uses an ion exchange filter, often termed a DI cartridge, which chemically traps ions. The filter has two aspects: one is negatively charged, and the other is positively charged. By passing water through this cartridge, it ensures the water interacts with both sides of the cartridge simultaneously.

The negative side of the particle attracts positive ions from the water while repelling the negatively charged ones, resulting in pure water devoid of contaminants like salts, metals, and minerals. Typically, deionization is a choice for commercial and medical setups, where ultra-pure water is indispensable.

Hard Water

The presence of dissolved minerals like calcium and magnesium defines hard water. These minerals cause the infamous “hard” trait of such water and create issues in domestic setups. Hard water can block pipes, lead to scale deposits on appliances, leave residues on dishes, hinder soap efficiency, and result in dry skin and hair.

Dealing with hard water is not just a matter of comfort but economy. Such water demands more energy from appliances, leading to escalated utility bills. Curious about the quality of water in your home? Culligan of St. Joseph offers complimentary water testing!

Soft Water

Soft water is the ideal choice for households. With minimal mineral content, it’s excellent for cleaning and personal care. Soft water doesn’t leave residues, ensuring smooth skin, and lustrous hair. The signs of hard water are evident: dry skin, dull hair, and at times, skin irritations. Thankfully, the adverse effects of hard water can be offset by using soft water.

Want optimal water quality for your household? At Culligan Water of St. Joseph, we align with your needs to offer tailored water solutions – from water softeners and delivery to advanced RO systems. Book a FREE water test with our specialists today!