Removes scale, rust, algae, and calcium deposits from bath tubs, wash basins, and swimming pools. It keeps fixtures sparkling, cleans urinals quickly and safely, gives off no odors or fumes, and is harmless to septic tans when used as directed. Application: Toilets; Fixtures; Applicable Material: Porcelain; Metal; Chemical Compound: Hydrochloric Acid; Dirt Types: Scale; Rust; Algae; Calcium Deposits.. Removes scale, rust, algae, and calcium deposits from bath tubs, wash basins, and swimming pools. It keeps fixtures sparkling, cleans urinals quickly and safely, gives off no odors or fumes, and is harmless to septic tans when used as directed.