5-Stage Tank Reverse Osmosis

Conventional · pressurised storage tank

The conventional under-sink arrangement, and one that has earned its reputation. Five stages feeding a pressurised reserve.

Water works through the cartridge stack and the RO membrane at its own pace, filling a pressurised storage tank. Your dedicated faucet draws from that reserve, so there is always purified water ready to pour.

The tank matters more to how one of these performs than people expect, which is why it is worth saying what is in it.

Key features

• High-strength steel shell with corrosion-resistant construction.
• Food-grade butyl bladder separating stored water from the air charge, which prevents contamination and keeps the water fresh.
• Pre-pressurised sealed air chamber for consistent flow at the faucet and less strain on the membrane, extending the life of the system.
• Compact footprint with a reinforced base — fits under most kitchen sinks while holding enough for drinking, cooking, coffee and a refrigerator ice line.

The filtration stages

• Stage 1 5-micron polypropylene sediment pre-filter to extract suspended material.
• Stages 2–3 Double NSF carbon block filters for chlorine by-products such as chloramine, THM and TCE, filtering organic matter without releasing carbon fines.
• Stage 4 NSF thin film composite RO membrane, 100 GPD, rated by its manufacturer at 95–99% rejection across total dissolved solids and heavy metals.
• Stage 5 In-line NSF coconut shell GAC filter to remove dissolved gases, taste and odour from the product water.

Specifications

Backed by a lifetime warranty

Lifetime on system dry parts, 5 years on the control valve, circuit board and filtration media, and 1 year on installation labor. Full terms on the warranty page — written out in plain language so you can read them before you buy.

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