Preparation

The second method was easier to make but at the same time, it was very tiring because they have to pour mana every single time they wanted to activate it. 

Of course, there was an easier method.

It was to put non elemental magic core on top of the five stones drawn with formation that has been fixed on the well. The formation would use the mana contained within the non elemental magic core and allowed the water that passed by the formation to be purified.

Based on what she knew, rank 1 non elemental magic core should last 1 month if they didn't overuse it.

Overusing it meant that they activated the formation 24 hours every single day.

Because if they did that, they would use up the mana within the non elemental magic core within half a month.

This number was only estimation and the application would still depend on the quality of the formation itself.