Self-cleaning tank

A method comprising:

• supplying power to a hydraulic motor with a hydraulic power unit, the hydraulic motor being attached beneath a tank and the hydraulic power unit separate from the tank, the tank including:
• a top surface;
• a solid bottom surface opposite the top surface,
• a wall fixed between the solid bottom surface and the top surface, and
• an aperture arranged in the wall of the tank;
• wherein the hydraulic motor is operatively coupled to a scraper blade assembly, the scraper blade assembly including:
• a blade rotatably coupled to the solid bottom surface of the tank,
• one or more bottom scraping members arranged on a leading surface of the blade to contact the bottom surface of the tank,
• a first scraping member attached to a first end of the blade, and
• a second scraping member attached to a second end of the blade;
• wherein when the hydraulic motor is powered by the hydraulic power unit the blade is rotatably displaced along the solid bottom surface of the tank, and
• wherein when the blade is rotatably displaced along the solid bottom surface of the tank,
• the one or more bottom scraping members maintain contact with the bottom surface of the tank, and
• at least a portion of the first scraping member and at least a portion of the second scraping member extend through the aperture when the first scraping member and the second scraping member pass by the aperture to displace solids deposited on the bottom surface of the tank through the aperture to clean the tank.