Which size do I need?
Which size do you actually need?
The most common mistake in this category is buying too small, running out of hot water, and concluding the geyser is faulty. Three questions will settle it.
Rough rule of thumb
| 1–2 people, buckets | 15 L |
| 3–4 people, buckets | 25 L |
| 1–2 people, showers | 25 L |
| 3+ people, showers | 25 L, and expect to stagger |
A shower uses roughly two to three times the hot water of a bucket for the same wash.
Why not just buy the biggest?
A larger tank costs more to buy and slightly more to keep hot, because there is more water losing heat overnight. Oversizing by one step is sensible; oversizing by two is money spent on standing loss.
Undersizing, though, is the mistake you notice every single morning.