JoJo Tanks and Backup Water Systems: What to Plan Before You Install One

A JoJo tank (or any backup water storage tank) is one of the more straightforward upgrades an Alberton or East Rand homeowner can make, but the plumbing side is where most of the actual decisions live — tank size, where it connects, and whether it’s gravity-fed or pump-assisted all change the cost and the result. Here’s what to actually think through before installing one.

What a backup tank does — and doesn’t do

A stored water tank is a buffer, not a treatment system: it holds municipal water (or harvested rainwater) so you have a supply during a water outage, but it doesn’t purify anything on its own unless you add filtration separately. For most Alberton households the goal is simple — keep the toilets flushing, the taps running, and ideally the geyser fed during a municipal supply interruption, without relying on bottled water or a generator-style panic response every time the area’s water gets cut.

Sizing the tank correctly

Tank size is usually the first thing people get wrong — either oversizing for a budget that doesn’t need to stretch that far, or undersizing and running dry within a day of an outage. A rough household guide: 750L–1,000L covers a couple of days of essential use (toilets, basic washing) for a small household; 2,500L+ tanks are more realistic for a family home wanting several days of comfortable backup, or for anyone also wanting to run a garden or pool top-up off the same supply. The right number depends on household size and how much you’re trying to cover — worth working out actual daily usage litres rather than just picking a popular tank size off a supplier’s shelf.

Gravity-fed vs. pump-assisted

This is the plumbing decision that actually matters most. A tank mounted high enough (on a stand, or fed from a JoJo tower) can supply water to ground-floor taps and toilets by gravity alone — no pump, no power dependency, which matters a lot if the water outage coincides with load shedding. A ground-level tank, or one that needs to reach upstairs bathrooms or maintain normal household pressure, needs a pressure pump — which adds cost, adds a point of failure, and means the backup system itself depends on power (so it’s worth planning for that, whether via an inverter or accepting the tradeoff).

Connecting into the household plumbing

There are two basic approaches: a standalone tap off the tank for manual use (buckets, watering cans, topping up during an outage), or a proper plumbed-in connection with a changeover valve that lets the house draw from either municipal supply or the tank automatically. The second option is far more convenient day-to-day but needs to be done correctly — a backflow prevention device is essential wherever a tank connects into the same plumbing as the municipal line, so stored water can never siphon back into the municipal system. This isn’t optional; it’s a genuine cross-contamination risk if skipped.

Where the tank actually goes

• Height matters for gravity feed — even a modest stand improves pressure without a pump
• Keep it off direct structural loads unless the stand or base is engineered for a full tank’s weight (a full 5,000L tank weighs 5 tonnes)
• Position near an existing downpipe if you’re also planning to harvest rainwater into it later
• Leave access for cleaning — sediment builds up over years even with a covered tank

What a proper installation quote should include

The tank and stand itself, the plumbing connection into the house (with backflow prevention where relevant), a pump and its wiring if the setup needs one, and clear guidance on what the system will and won’t cover during an outage. If a quote only covers “drop the tank on a stand,” the plumbing connection — the part that actually makes it useful — is being left for a second job later, usually at extra cost. Better to plan and quote it as one project from the start.