A swimming pool is a watertight box with a series of deliberate holes in it. Skimmers, lighting and inlets all have to pass through the shell, and every one of those penetrations has to be sealed. All other pool constructions on the market use traditional built-in parts that are made watertight with rubber seals.
Although proven, every rubber seal remains a potential risk of leakage, both in the short and in the long term. Rubber is a different material from the shell around it: it ages differently, expands differently and reaches the end of its service life on its own schedule, usually long before the pool does.
