Clean, safe, and great-tasting drinking water is not a luxury; it’s a necessity for every home in Bangladesh. For families considering a Reverse Osmosis (RO) system to achieve this, the first and most crucial decision often boils down to a single, central dilemma: should you choose a 5-stage or a 6-stage RO filter?
This choice can be confusing. What does that extra stage actually do? Is it an essential upgrade for your health or an unnecessary expense? Understanding the difference is key to making the right investment for your home.
At WaterMan BD, we’re here to clear the confusion. This guide will break down the differences, pros, and cons of 5-stage vs. 6-stage RO filters to help you make the most informed and confident choice for your family’s health and your water quality needs.
The Standard 5-Stage RO System: A Proven Workhorse
A 5-stage RO system is the industry standard for a reason. It effectively removes a vast majority of contaminants found in water.
The 5 Stages:
 | 1. Sediment Filter: The first line of defense. This pre-filter removes dirt, dust, rust, and other suspended particles. 2. Pre-Carbon Filter: Removes chlorine, chloramines, and other chemicals that affect taste, odor, and can damage the delicate RO membrane. 3. RO Membrane: The heart of the system. This semi-permeable membrane removes up to 99% of dissolved solids, including heavy metals (arsenic, lead), salts, fluoride, and viruses/bacteria. 4. Post-Carbon Filter: Also known as a “polishing” filter. It further improves the taste and odor of the water after it leaves the storage tank. 5. Ultraviolet (UV) Light Chamber (Common in Bangladesh): A crucial stage for Bangladeshi water sources. The UV light sterilizes the water, eliminating any remaining microorganisms like bacteria and viruses, providing a final layer of protection. |
Pros of a 5-Stage RO System:
Comprehensive Purification: Effectively removes physical, chemical, and biological contaminants.
Proven Technology: A reliable and widely used system with readily available replacement filters.
Cost-Effective: Generally more affordable upfront and for maintenance compared to a 6-stage system.
Ideal for Most Water Sources: Perfect for municipal tap water in cities like Dhaka, Chattogram, etc., which may have medium TDS (Total Dissolved Solids).
Cons of a 5-Stage RO System:
May Remove Some Beneficial Minerals: The RO membrane is so effective that it also strips water of natural minerals like calcium and magnesium.
Produces Wastewater: The reverse osmosis process requires water to rinse the membrane clean, leading to some water wastage (though modern systems are more efficient).
The Advanced 6-Stage RO System: Enhanced Purity & Health
A 6-stage RO system includes all the features of a 5-stage system but adds one crucial extra stage: a ‘Mineral Cartridge’ or an ‘Alkaline/pH Booster’.
The 6th Stage: What is it?
Mineral Cartridge (Most Common): This stage adds back essential healthy minerals like calcium, magnesium, and sometimes potassium into the purified water. This addresses the primary concern of demineralized water.
Alkaline/pH Booster: This filter not only adds minerals but also raises the pH level of the water, making it less acidic. Some believe alkaline water has additional health benefits, though these are debated.
Pros of a 6-Stage RO System:
All Benefits of 5-Stage: You get the same thorough purification.
Restores Beneficial Minerals: The water not only is pure but also contains minerals that are good for bone and metabolic health.
Improved Taste: Many people prefer the taste of mineralized water over completely neutral RO water.
Potential Alkaline Benefits: For those seeking alkaline water, this is an integrated solution.
Cons of a 6-Stage RO System:
Higher Cost: The initial purchase price and the cost of the additional filter during maintenance are higher.
May Not Be Necessary: If your diet is already rich in essential minerals, the added benefit might be marginal.
Complexity: An extra stage means one more filter to replace periodically.
Side-by-Side Comparison
| Feature | 5-Stage RO System | 6-Stage RO System |
| Core Purification | Excellent | Excellent |
| Removes Minerals? | Yes | Yes, but adds them back |
| Taste | Clean, Neutral | Crisp, often “softer” or mineral-like |
| Best For | Standard municipal water sources | Those seeking mineral-enriched or alkaline water |
| Upfront Cost | Lower | Higher |
| Maintenance Cost | Lower (fewer filters) | Higher (extra filter to replace) |
| Ideal TDS Level | Medium to High TDS | Can handle all TDS levels; improves low-TDS output |
So, Which One is the Best Choice for You?
The “best” choice isn’t about the number of stages; it’s about which system best addresses your specific water quality and health preferences.
Choose a 5-Stage RO System if:
* Your primary water source is municipal supply with medium TDS.
* You are looking for a cost-effective solution for pure, safe drinking water.
* You get ample minerals from your daily diet.
* Your budget for both initial purchase and annual maintenance is a key consideration.
Choose a 6-Stage RO System if:
* You are concerned about the lack of minerals in purified water and want to ensure you consume them.
* You prefer the taste of mineral water.
* You are interested in the potential benefits of alkaline water.
* Your water source has very high TDS, and you want the extra assurance of mineral repletion.
* You are willing to invest more for an enhanced feature.
The WaterMan BD Recommendation
At WaterMan BD, we believe in personalized solutions. There is no one-size-fits-all answer.
Before recommending any system, our experts always advise a Free Water Test . We test your water directly from your tap to analyze the TDS level, hardness, and presence of contaminants. This scientific analysis, combined with an understanding of your family’s needs and budget, allows us to recommend the perfect system – whether it’s a robust 5-stage or an advanced 6-stage RO filter.
Still unsure? Let the experts guide you.
Schedule your FREE water test today! Contact WaterManBD to have our water specialist visit your home in Dhaka or anywhere in Bangladesh and provide a tailored recommendation.
Ensure your family’s health isn’t left to chance. Choose the right purification with confidence.
