> The brick needs to be completely dried out to attain the maximum structural capacity (i.e., strength), but at the same time, drying stresses the bacteria and compromises its viability. To maintain structural function and ensure microbial survivability, the concept of optimum relative humidity and storage conditions is critical. Utilizing the humidity and temperature as physical switches, the researchers can control when the bacteria grow and when the material stays dormant to serve structural functions.
So it can't get wet.
> they use light from the sun to grow and proliferate with very little exogenous material needed for their growth
Do the bacteria just die after the initial nutrients run out?
It can get wet, but just not too wet. And it doesn't necessarily die when the initial nutrients run out as long as more naturally enter. The solution is to deal with sub-maximal strength and provide a slow nutrient drip(or possible occasional soaking with a nutrient slush).
So it can't get wet.
> they use light from the sun to grow and proliferate with very little exogenous material needed for their growth
Do the bacteria just die after the initial nutrients run out?