RR1-30 Rid O' Rust Rust Stain Preventer 2x Well Water Stain Preventer Concentrate REPLACES FORMULA 500 & 2000 Prevents rust and lime scale staining caused by well-based irrigation 30 gallon Drum 1- 30 gallon Drum of RR1 is equal to 1- 30 gallon Drum of Formula 500 1- 30 gallon Drum of RR1 is equal to 1- 60 gallon Drum of Formula 2000