* Specifications of the inner and outer layers of the tank:-

Firstly:
The inner layer: It is a white layer so that the users of the tanks can know the degree of purity of the water, and this layer is smooth to reduce the possibility of algae and bacteria sticking to the inner wall of the tank.
Secondly:
The middle layer: It is a black layer, by adding black carbon material at a rate of 2%, as this material absorbs high-frequency ultraviolet rays, which may affect the tank material.
Third:
The outer layer: It is a white layer to reflect the most sunlight.

* Features of polyethylene tanks:-
1- The tanks are designed to be supported by circular belts from the outside, which reduces the water pressure on the sides of the tank, and thus helps to increase its life span.
2- The upper opening of the tank was designed to be wide enough for the entry of a person to perform the installation of connections from the inside, which would facilitate the cleaning process of the tank after that.
3- The best grade of polyethylene was chosen only for the manufacture of tanks, which is characterized by being non-toxic, ensuring purity and coldness of water and does not cause water odor and is authorized for use in packing foodstuffs, as well as it is characterized by good flexibility, which prevents the tank from cracking when any collision or fall from Simple heights.
4- Equipped with four upper knees from the top of the tank to balance the tank from the top.
5- Lightweight and easy to install.
6- 3-year warranty against manufacturing defects.
7- The tanks conform to the Egyptian standard specifications and have a permit from the Educational Buildings Authority.