AquaGuard Whole-House Filter

Only 26 of South Africa's 958 municipal water systems scored above 95% in the last Blue Drop audit. The fix at the plant is more chlorine. The fix in the street is nothing, because the mains are decades old and shedding rust and sediment into the supply.

Pull a cartridge out of any Johannesburg home after five months and look at the colour. That is what was going into the geyser, the washing machine and the shower.

1. 5 micron sediment. Rust, sand, mud and the visible load.
2. Carbon block. Chlorine, chemical taste and smell, plus a second 5 micron pass.
3. 1 micron sediment. The fine particles the first two let through, and the polish a UV steriliser needs.

Three 20 inch Big Blue housings pass 2 720 litres an hour, so the shower does not notice the filter is there.

Two signs, and a third if you want certainty. The shower slows, or the cartridges reach six months. For certainty, have a pressure gauge fitted either side of the unit when it goes in: with a tap running, fresh cartridges read about 0.2 bar apart, and at 0.7 bar they are full and it is time for the set. No guessing, no changing early, no running blocked.

Inlet and outlet are 1 inch female BSP. The frame stands on the ground or bolts to a wall beside the meter. Fit an isolation valve before it, and a bypass if you want to change cartridges without shutting the house. Most plumbers fit it in under two hours; Andy Plumbers, our own team, does it anywhere in Johannesburg, and a photo of the meter on WhatsApp gets you a price the same day.

Add the 55 watt UV steriliser after the third stage for bacteria, viruses and cysts. The combo puts both in one order with the adaptors that join them.