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How Much Water Does a Family Use Per Day? Sizing Tanks, Pumps and Purifiers
- Total use: about 50–100 L per person per day
- Drinking and cooking: only about 2–4 L per person per day
- Store at least 1–2 days of total use
- A small under-sink RO covers a whole family's drinking water
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Quick household calculator
| Household | Total per day | Drinking & cooking | Suggested storage |
|---|---|---|---|
| 2 people | 100–200 L | about 4–8 L | 500 L |
| 5 people | 250–500 L | about 10–20 L | 1,000 L |
| 8 people | 400–800 L | about 16–32 L | 1,500–2,000 L |
Sizing the storage tank
Hold at least one to two days of total use so water cuts do not leave you dry. Tanks from our shops:
| Product | Price |
|---|---|
| 500l Reliance water storage tank | KSh 5,500 |
| 1000L Reliance Loft Tank – No More Water Shortages! | KSh 12,500 |
Current listed prices incl. VAT (updated 30 September 2026).
Sizing the pump
A booster pump with a pressure controller gives steady pressure to taps and showers; size by the number of outlets used at once. See how to choose a water pump.
Sizing the drinking-water purifier
Because drinking water is a small share of use, a home RO or UF purifier is small and affordable:
20Lph DOMESTIC WATER PURIFIERKSh 35,000
80ltrs/hr DOMESTIC WATER PURIFIERKSh 100,000
UF Under Counter System (5 Stage)KSh 17,000
RO Under counter system, without booster pumpKSh 30,000
RO Under counter system, with booster pumpKSh 35,000
7 stage Domestic water purifierKSh 42,000| Model | Size / capacity | Price |
|---|---|---|
| 20Lph DOMESTIC WATER PURIFIER | 20 LPH | KSh 35,000 |
| 80ltrs/hr DOMESTIC WATER PURIFIER | 80 L | KSh 100,000 |
| UF Under Counter System (5 Stage) | – | KSh 17,000 |
| RO Under counter system, without booster pump | – | KSh 30,000 |
| RO Under counter system, with booster pump | – | KSh 35,000 |
| 7 stage Domestic water purifier | – | KSh 42,000 |
| RO-400G-D02B 5-Stage RO System | – | KSh 98,000 |
Current listed prices incl. VAT (updated 30 September 2026). Full range: RO water purifiers price list.
Frequently asked questions
How much water does one person use per day?
Roughly 50–100 litres for all uses; only about 2–4 litres is for drinking and cooking.
What size tank does a family of five need?
About 1,000 litres covers one to two days for most families of five.
Do I need a big purifier for my house?
No. Purify only drinking and cooking water; a small under-sink unit is enough.
How do I get steady water pressure?
Use a booster pump with a pressure controller from your tank.