Black Knight 4" Dia x 12" Long Filter Brushes - 6 Pack aquacolour-black Dual Sponge Filtration: Two separate

Dual Sponge Filtration: Two separate sponge cartridges provide effective mechanical and biological filtration

Dual Use: Compatible with both freshwater and saltwater systems

in amounts fish consume within minutes

Dual Range 0-9990 ppm (From 0 - 999 ppm the resolution is 1 ppm

Black Knight 4" Dia x 12" Long Filter Brushes - 6 Pack aquacolour-black Dual Sponge Filtration: Two separateWhat are Black Knight Filter Brushes: Black Knight filter brushes are made from the very highest quality Hydrotek polypropylene twisted into two stainless steel wires to form a cylindrical brush with a loop at one end for hanging. The other end is capped with a plastic knob for safety. They last indefinitely and are the easiest to use, most efficient and most cost effective pond filter medium you can buy. Our brushes are used in filtration systems in