There is a pigment that is found in rock and gravel businesses that is added to the plaster mix under certain formula measurements.
k
It depends one what pool you go to. There are some swimming pools that have lines on the bottom and there are others that do not
I did a basic Google search and found the site: Cheers.
lakes or pools
Compared to a black hole, they are mere puddles. bottom less
Under no condition do fiberglass pools have "ripples" on the bottom after they are installed. Of course, the pool could have been damaged in some way, then improperly repaired, before or after it was installed.
The water sinks and pools at the bottom of the tank
Yes. We had a black/brown pepple tec installed over our stained concrete pool and it does make the water a little warmer. Not significantly but noticeble enough to enjoy a quick dip.
Yes they are, seeing the bottom of a dark bottomed pool is not difficult at all contrary to the opinions of some
deep enough for no one to be able to touch the bottom
The Benthic Zone.
It sounds like some sort of algae when you expose it to the pools water it brings it under controll.
A pool divided into lanes has a bottom painted with black stripes, dividing the lanes apart. There are also heavy ropes stretched from one end of the pool to the other, dividing the lanes apart.