Recommended Cleaning Frequency
For residential properties in Harare and Bulawayo, clean and sanitize your storage tanks every 6 to 12 months, or whenever noticeable sediment or discoloration appears at the taps.
1. Why Sediment and Algae Accumulate in JoJo Tanks
Even clean borehole water contains naturally occurring dissolved minerals (such as iron, manganese, and calcium). When water stands motionless in large 2,500L, 5,000L, or 10,000L tanks, these minerals gradually settle at the base, forming a fine brown sludge.
Algae growth, on the other hand, requires two elements: sunlight and nutrients. If your tank lid is loose, unsealed, or if light penetrates through thin tank walls, microscopic airborne algae spores quickly multiply, coating the interior with slippery green biofilm and creating musty odors.
2. Step-by-Step Guide: How to Deep Clean Your Tank
Isolate & Drain the Tank
Turn off your booster pump and close the inlet line connected to your household plumbing to prevent dirty water from entering home pipes. Open the bottom scour / drain valve to empty the tank, leaving roughly 15–20cm of water at the base to assist with scrubbing.
Scrub Walls & Agitate Bottom Sludge
Use a clean, stiff-bristled non-metallic broom or brush with a long handle. Thoroughly scrub the internal tank walls from top to bottom to dislodge biofilm, algae, and scale. Swirl the bottom water to suspend the silt into a slurry.
Flush & Evacuate Slurry
Open the bottom drain outlet or use a wet vacuum / submersible puddle pump to completely remove the dirty sludge. Rinse walls down with fresh water until the discharge runs completely transparent.
Disinfect & Sanitize (Chlorine Rinse)
Mix a mild sanitizing solution (50ml of unscented household bleach per 10 litres of water). Using a clean pressure sprayer or sponge mop, wipe down all interior surfaces. Let it stand for 30–60 minutes to neutralize all remaining bacteria and algae spores, then perform a final rinse.
Schedule a Fresh Bulk Bowser Refill
Once clean and drained, book a fresh delivery from 247 Bulk Water Network. We pump pristine borehole water directly into your clean tank at high pressure, providing fresh domestic storage.
3. 5 Golden Rules to Prevent Algae Growth Long-Term
1. Block 100% of Sunlight
Always keep the heavy-duty inspection lid screwed on tight. If your tank is light-colored or semi-translucent, paint the exterior with a UV-stable dark coat to block light penetration completely.
2. Install Inlet Mesh Strainers
Fit fine stainless steel mesh over all vent pipes and tank inlet openings to block leaves, insects, lizards, and windblown dust spores from entering.
3. Elevate the Take-Off Valve
Ensure your booster pump suction pipe is connected 10–15cm above the tank bottom. This ensures naturally settling silt remains undisturbed at the base rather than entering your house taps.
4. Install an In-Line Disc Filter
Place a washable 100–120 mesh disc filter between the tank and your booster pump. This catches fine sediment before water reaches geysers, washing machines, and shower heads.
4. Ordering Your Post-Cleaning Bulk Water Refill
After completing your tank cleanout, 247 Bulk Water Network provides rapid delivery bowsers tailored to your storage setup across Harare, Bulawayo, Chitungwiza, and Norton:
| Tank Size | Recommended Refill Volume | Delivery Time |
|---|---|---|
| Small 1,000L / 2,000L Tanks | Less than 2,500 Litres | Same-Day / Scheduled |
| Standard 5,000L JoJo Tank | 5,000 Litres | Immediate Rapid Dispatch |
| Dual 5,000L / 10,000L Setup | 10,000 Litres | Single 10kL Bowser Trip |
| Cluster Complexes / Commercial | 15,000L – 20,000L+ | Heavy-Duty Bowsers |
5. Suburbs Serviced Across Greater Harare
Our dispatch fleet operates continuous delivery loops across: