Key points
- A 5,250L JoJo tank retails from around R6,499 at Builders; a 10,000L JoJo costs R19,902-R21,756 at plumblink.co.za, while the equivalent Nel Tanks unit lists at R18,550.
- The tank is rarely the biggest line item. Turnkey installation of a 5,000L system runs R18,000-R28,000 once you include the base, pump, pipework, and a PIRB-registered plumber for the compliance certificate.
- Every plastic tank loses some capacity to dead volume at the bottom; budget on 85-90% of nominal capacity being reliably usable.
- Legal connection to the municipal supply line requires SANS 10252 compliance and a Plumbing Compliance Certificate from a PIRB-registered plumber.
Why South African homeowners are buying tanks right now
Tshwane municipality alone spent R777 million on emergency water-trucking tenders, according to businesstech.co.za. That single figure explains the queues at hardware stores and the four-to-six-week lead times on large tanks in Gauteng and the Western Cape. Electrical faults at major substations knocked out bulk pumping at Rand Water’s Vereeniging and Eikenhof plants, causing widespread municipal outages across Gauteng and illustrating exactly how vulnerable supply is to load-shedding. Water interruptions that once lasted hours now stretch to days, and load-shedding compounds the problem by knocking out municipal pump stations at the same time.
Leon Basson, chairperson of the Portfolio Committee on Water and Sanitation, has warned that expensive emergency water-tankering is becoming a permanent, lucrative business at the expense of real infrastructure repairs, a pattern that makes a home backup tank a far more reliable long-term answer than waiting on a municipal water truck. Nationwide public hearings on the Water Services Amendment Bill have highlighted deep public anger over dry taps and broken infrastructure, reinforcing why backup water storage has moved from a rural or smallholding concern to a mainstream suburban necessity.
This article cuts through the marketing and gives you verified prices, real installation costs, honest capacity figures, and what owners discovered only after the tank was in the ground.
True capacity: what the label does not tell you
Manufacturers quote nominal capacity, not usable capacity. Three engineering realities eat into that headline number every time.
Bottom dead volume. The pump strainer never reaches the lowest point of the tank floor, so a few centimetres of water always remain inaccessible (Flocea). University of Johannesburg researchers note that round cylindrical tanks act as completely mixed vessels, which means sediment and biofilm circulate rather than settling cleanly.
“My only gripe is the tank size, that 1000L tank gives you 840 usable litre. Wish I could fit, at least, a 2500L tank.”
Mannydefreitas, MyBroadband SA Forum (March 2024)
Float valve and level-switch headroom. Alpha Controls confirms that float valves and level switches must be hung with adequate space, real headroom below the overflow level and real margin above the outlet. In practice, this reserves another 3-5% of nominal volume as a mechanical buffer you cannot use for supply.
Sediment accumulation. A member of the Facebook Rainwater Harvesting Community put it clearly:
“Each tank has about 5 cm of dead volume where these [sediments] can accumulate and be cleaned out every once in a while. If they make it into the pump it is also not a big deal as they should be able to pass easily…”
Facebook Rainwater Harvesting Community member, August 2026
The practical rule: budget on 85-90% of the nominal capacity being reliably usable for a well-maintained above-ground tank on municipal supply. A nominal 5,250L JoJo gives you roughly 4,460-4,725 litres of pressure-pumpable water on any given day.
JoJo updated its moulds for popular sizes, so what was sold as a standard 5,000-litre tank is now produced as a 5,250-litre unit (SA Property Tools). That 250 litres is a genuine gain, not a marketing rounding error.
Brand-by-brand breakdown
JoJo Tanks
The dominant brand in South Africa for good reason. Above-ground tanks are manufactured from 100% virgin food-grade LLDPE (jojo.co.za), which matters because recycled-content plastics vary in UV stabiliser concentration and food-safety certification. JoJo explicitly uses recycled plastics only for underground septic and conservancy tanks.
The black interior liner that JoJo is known for does generate owner concern occasionally. One owner raised an alarm online:
“Anyone that has installed [a] backup water system using Jojo tanks, you should check the black lining inside the tank. Our tanks have been in less than 3 years and the lining is coming off… so one has to assume this includes the algae resistant lining.”
Facebook user on tank liner concerns
That story had a resolution worth noting. JoJo responded promptly and investigated:
“Jojo reacted fast, and Jeremy has been on site, and it has been confirmed THE LINER IS STILL INTACT…. it is a very fine sediment on the bottom of the tank. Will need to install very fine filter on the incoming line to stop this sediment entering tank from municipal water supply.”
The same owner, updating the community after the site visit
This is a meaningful data point: the black material was municipal sediment, not a failing liner. It also illustrates why a 5-micron PP pre-filter (replacement cartridge: R349 at builders.co.za) and the JoJo Disruptor cartridge (R499 at builders.co.za) are not optional extras for anyone on a municipal supply with ageing pipes.
JoJo advises rotating water every two weeks for tanks on municipal supply (jojo.co.za). If your household usage is lower than the tank volume divided by 14 days, you need to actively flush the tank, not just wait for natural drawdown.
One owner on the Highveld noted a practical cold-weather issue:
“Had to repair the JoJo tank tap (my own fault, but it broke due to brittle plastic)”
Owner discussing plastic embrittlement from freezing temperatures
Peripheral fittings, not the tank wall itself, are the first failure point in cold climates. Insulate or lag exposed fittings if you are in the Highveld interior.
Nel Tanks
Nel Tanks offers a 10,000L vertical unit at R18,550 (neltanks.co.za), making it R1,352-R3,206 cheaper than the equivalent JoJo depending on which JoJo retailer you use (plumblink.co.za quotes R19,902-R21,756). The saving is real and meaningful. The warranty fine print, however, deserves attention: Nel Tanks states clearly that a pro-rata payment based on the period of use may be required in a warranty replacement (neltanks.co.za). That means a tank that fails in year four of a ten-year warranty could still cost you 40% of the replacement price out of pocket.
Eco Tanks
Eco Tanks voids its warranty if liquid contents exceed 40°C (ecotanks.co.za). For above-ground tanks positioned in full sun in Limpopo, Mpumalanga, or the Northern Cape, water temperature inside an unshaded tank can approach or exceed that threshold during midsummer. Shade cloth or a north-facing shaded wall position is not a cosmetic preference, it is a warranty condition.
Pricing table: hardware, installation, and running costs
| Item | Verified cost | Source |
|---|---|---|
| JoJo 2,700L / 2,750L tank (hardware only) | ~R5,149 | builders.co.za |
| JoJo 5,250L tank (hardware only) | ~R6,499 | builders.co.za |
| JoJo 10,000L tank (hardware only) | R19,902-R21,756 | plumblink.co.za |
| Nel Tanks 10,000L tank (hardware only) | R18,550 | neltanks.co.za |
| Concrete foundation / base | R800-R2,000 (up to R2,500 for commercial premix) | Research findings |
| Basic pressure pump | R2,500-R5,000 | Research findings |
| Full 2,500L system, turnkey installed | R12,000-R18,000 | Research findings |
| Full 5,000L system, turnkey installed | R18,000-R28,000 | Research findings |
| JoJo 5-micron PP sediment pre-filter cartridge | R349 | builders.co.za |
| JoJo Disruptor replacement cartridge | R499 | builders.co.za |
| Basic lab water test (E. coli, pH, TDS) | R850-R1,200 per sample | Research findings |
What real installation quotes look like
The gap between the hardware price and the total project cost is where most buyers get a shock. The forum record on this topic is unusually rich and worth quoting directly.
“Got a quote from an installer… I paid for a Jojo and the pump, and they quoted me 35K to install everything (it will need a concrete block for levelling). This seems….far too much?”
Pansyfaust, MyBroadband Forum, 2025
“Way too much, I paid R29k including the pump and tank (which itself was R5k more due to being a slimline). Total cost would have been R24k if I went with a normal tank. They even had to buy extra piping which they didn’t charge for…”
Mike Hoxbig, MyBroadband Forum, 2025, responding to the above
“I was quoted R20k for a 2500lt tank including all fixtures and copper piping, the ground needs to be leveled, tank mounted against wall and lifted on lintels, lever valve and the electric box and power pump.”
amiechankawaii, Reddit r/johannesburg, 2023
A DIY owner broke down his actual spend in detail:
“I did mine myself and it cost me probably about R11k. Concrete slab – R2500 (I used premix, but would be cheaper if I bought individual cement, sand and stone) 2500L africa tank – R2000 DAB Pump – R2000 (usually R4500, got it on clearance) Jojo tank float – R300.”
Mzezman, MyBroadband Forum, 2023
The spread between a R11,000 DIY job and a R35,000 installer quote for functionally similar systems is not fraud, it reflects real variation in labour rates, pipe runs, electrical work for the pump, and whether the plumber issues a Plumbing Compliance Certificate. That COC is legally required when you tie a backup tank into the municipal supply line under SANS 10252, and only a PIRB-registered plumber can issue it. If a quote does not include the COC, add that cost; the legal exposure if you skip it is yours, not the installer’s.
Not sure which system suits your address and your municipality’s outage history? Check my address to get a sizing recommendation based on your specific location.
Cost-of-ownership comparison: 2,500L vs 5,000L vs 10,000L over five years
| Cost element | 2,500L system | 5,250L system | 10,000L system |
|---|---|---|---|
| Tank hardware | ~R5,149 | ~R6,499 | R18,550-R21,756 |
| Base / foundation | R800-R2,500 | R800-R2,500 | R1,500-R2,500 |
| Pump | R2,500-R5,000 | R2,500-R5,000 | R3,500-R5,000 |
| Pipework, float valve, fittings, labour (PIRB plumber) | R3,500-R8,000 | R5,000-R10,000 | R6,000-R12,000 |
| Filter cartridges over 5 years (annual replacement) | ~R4,240 | ~R4,240 | ~R4,240 |
| Water testing (one test per year at R1,000) | ~R5,000 | ~R5,000 | ~R5,000 |
| Indicative 5-year total (mid-range) | ~R21,000-R30,000 | ~R24,000-R33,000 | ~R39,000-R51,000 |
The filter cartridge figure above assumes one 5-micron pre-filter replacement (R349) and one JoJo Disruptor cartridge replacement (R499) per year, totalling R848 per year, or approximately R4,240 over five years. Water testing is listed as optional but strongly recommended when you store water for drinking or cooking, a basic E. coli, pH, and TDS panel runs R850-R1,200 per sample (research findings).
A pump running at moderate output for occasional use during outages adds a negligible electricity cost, as one Reddit r/johannesburg user confirmed: “I didn’t notice any electricity usage spikes, even when we used the pump quite often during week long outages.”
The five most common operational problems and how to avoid them
1. Water hammer
One MyBroadband user described the problem precisely: “the pump switches on whenever any pressure drop occurs and your taps will suffer from water hammer effect every time… I also suspect this constant water hammer will cause cavitation in the pump and thus reduce its life.” The fix is a pressure vessel (accumulator tank) sized to your pump, and a pump with a variable-speed drive or a built-in pressure switch with adequate hysteresis.
2. Float valve failures at night
Municipal pressure often returns at low-demand hours, typically between midnight and 4am. One owner described the reality: “Love is getting up at 12, 2 and 4am to check that my overflow pipe into the second tank is working.” A quality float valve rated for the highest expected municipal pressure, plus a ball-valve isolator you can close before bed during irregular supply, solves this.
3. Stagnant water and bacterial blooms
A MyBroadband user noted: “Most online articles advise against letting grey water sit for more than 24 hours due to bacteria, sludge and smell.” Even clean municipal water stored without UV blocking can develop bacterial counts over time. JoJo’s own guidance is to rotate water every two weeks. If your household is small relative to tank size, this discipline is non-negotiable.
4. Oversized tanks on undersized budgets
The old rule of thumb, roughly R1 per litre for the tank hardware, no longer holds for the larger sizes. In practice, a 5,250L JoJo at R6,499 is closer to R1.24 per litre, and a 10,000L unit at around R20,000 is R2 per litre. The unit cost rises with size, not falls, until you reach very large commercial tanks. Budget accordingly.
5. Sizing too small
The advice from experienced owners is consistent: store as much as your space and budget allow. As one owner put it: “Hold as much water as space affords, and finances allow. These tanks keep water cool and alkaline… Money well spent.” The risk of under-sizing is not just inconvenience, during a multi-day municipal failure, a 1,000L tank is gone in under two days for a household of four. Johannesburg Water’s 96-hour winter maintenance shutdown is a recent reminder of how long a planned outage can run.
What to check before you sign any installation quote
- Is the installer PIRB-registered? Ask for their PIRB number and verify it. Without a registered plumber, you cannot get a Plumbing Compliance Certificate, and connection to the municipal line is non-compliant under SANS 10252.
- Does the quote include the concrete base? A R2,500 premix slab is easy to omit from a headline figure and easy to argue about after the fact.
- What pump is specified? A basic pressure pump runs R2,500-R5,000 at retail. If the quoted pump price is lower, ask for the make and model and check the warranty.
- Is a pre-filter included? Municipal supply in older South African suburbs carries fine sediment (the liner-scare story above confirms this). A 5-micron pre-filter costs R349 to replace but far more to install retrospectively if the pipework is already buried.
- Is delivery included? Large tanks (5,000L and above) require a truck with a crane or hiab. Delivery can add R600-R1,500 depending on distance and access. This is frequently excluded from retailer prices.
Ready to get a real tank installation quote?
The one question worth asking your installer before anything else
“How much usable storage will I actually have, after dead volume and valve margins, if the municipal supply fails for five days?” If the installer cannot answer that question with a specific number and a simple household daily-use calculation, find a different installer. A family of four in a suburban home uses roughly 600-800 litres per day for basic needs. That means a 5,250L tank at 88% usable capacity gives you about 4,620 litres, six to seven days of water independence. A 2,700L tank at the same usable fraction gives you three to four days. The numbers are not complicated, but they have to be done before the concrete is poured.
Not sure which tank size is right for your address, your erf, and your municipality’s outage history? Check my address to get a sizing recommendation based on your specific location.
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