The researchers studied how different levels of phosphorus affected the growth and photosynthesis of a type of marine algae called Chlorella sp. They found that the algae grew best and had the highest pigment content when exposed to a medium with 36.21 μmol/L of phosphorus. The algae's photosynthesis also improved with higher phosphorus levels, but too much phosphorus had a negative effect. This research shows that phosphorus concentration plays a crucial role in the growth and health of marine algae like Chlorella sp.