A network of modular, multitier pool mobile units, that wander around and under water of a swimming pool. The pool mobile units monitor for safety, emergency and accident related events and undertakes appropriate actions, scrub and clean the swimming pool, emit chemical agents to sanitize the swimming pool water, and may play music. The pool mobile units may simply operate on the pool surface, be fully submersible, or semisubmersible. A central server manages a plurality of multitier pool mobile units in a plurality of swimming pools, supports music download, and provides experience based resources for the multitier pool mobile units. The central server provides experience based resources in the form of safety, emergency and accident supports. The user can configure the parameters of both pool mobile unit and the central server.