The phrase "water lily" is used to describe aquatic plants which have lily pads.
The water lily's leaves shade the water keeping it cool and thus allowing for more dissolved oxygen.
Water Lily flowers are wonderfully showy and fragrant, lasting only a few days. Some open during the day and close at night, others the opposite.
On the other hand, the lotus bears fruits - nut like and delicious, but has far less nectar. In exchange for missing fruits the water lily has a daily high volume of sweetest nectar.
Seen and admired in the Blue Lotus Watergardens, Yarra Junction, Victoria Australia