i forget what their called but its a black or green sponge type thing. their made out of plastic.(it looks like plastic wire?) we use them up at my shop to clean the tanks. just use water and scrub. its not back breaking work and unless their really really bad it will take almost no effort on...
i forget what their called but its a black or green sponge type thing. their made out of plastic.(it looks like plastic wire?) we use them up at my shop to clean the tanks. just use water and scrub. its not back breaking work and unless their really really bad it will take almost no effort on...
