Hague H3500 Reverse Osmosis
Premium 4-stage RO with the longest membrane life we sell.
A high-output under-sink reverse osmosis system from the same engineers that build the WaterMax. Delivers bottled-quality water to a dedicated faucet at your kitchen sink — and to your fridge ice-maker if you want it.
Households that want the best-tasting drinking water available, with the lowest long-term filter cost.
What you get
- 4-stage filtration with high-rejection membrane
- High daily output — no waiting for the tank to refill
- Optional fridge / ice-maker hookup
- Designer faucet options (chrome, brushed nickel, matte black)
- Long-life sediment and carbon pre-filters
Specs at a glance
- Stages
- 4
- Tank
- Under-sink, ~3.2 gallons usable
- Faucet
- Dedicated, multiple finishes
“Customers stop buying bottled water within a week of install. Pays for itself faster than people expect.”
— The Sawtooth team
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DetailsInterFlo · ValueInterFlo IF-14 Drinking Water Filter
Single-cartridge under-sink filter for great-tasting cold water.
DetailsHague H3500 Reverse Osmosis — common questions
What buyers ask us before they choose this system.
How does reverse osmosis work?
Water is pushed through a semipermeable membrane that blocks dissolved solids, nitrates, lead, and most contaminants while letting water molecules through. Pre-filters catch sediment and chlorine before the membrane, and a carbon post-filter polishes taste on the way to the faucet. Filtered water is held in a small tank under the sink so it's there when you need it.
How often do RO filters need changing?
Pre-filters and carbon post-filters are annual on most systems. The membrane itself lasts three to five years, longer if the water is softened first — hardness is the main thing that shortens membrane life, which is why we usually recommend the softener and RO together.
Does reverse osmosis remove nitrates from well water?
Yes, and that's a real consideration in agricultural parts of the Magic Valley where nitrate levels in private wells can exceed the 10 mg/L drinking water standard. RO is one of the few point-of-use technologies that reliably reduces nitrates. If you're on a well and haven't tested for it, we'll include it in your free water test.
Can RO be plumbed to the refrigerator ice maker?
Yes — that's one of the most requested add-ons. We run a dedicated line from the RO tank to the fridge so ice and chilled water come from the same filtered supply. It's a straightforward addition during install and can be retrofitted later.