There are several reasons why your turtle's tank water might be cloudy. The most common reason is that the turtle's waste contains nutrients that the bacteria need to thrive. When the turtle eats, the bacteria are also able to multiply and spread to other areas of the tank. The turtle's shell serves as a perfect paradise for bacteria buildup, so it keeps the tank healthy and hygienic. It is essential that waste be removed frequently. Maintaining regular cleanings keeps your pet safe from an unhealthy home.