Answer:
I have a little pool with two layers of wall around it. One white and soft and the other dark and hard. Amidst a light brown grassy lawn with an outline of a green grass.
I can be found in water but never wet
2 in a corner 1 in a room 0 in a house but 1 in a shelter.
The Titanic is still here. What am I?
I am in the middle of water but am not an island.
No matter how little or how much you use me, you change me every month.