Bio Balls 500ml

Bio balls are a classic biological filter medium used primarily in wet-dry trickle filters and sump chambers. Their hollow, star-shaped plastic construction causes water to tumble and break into thin films as it cascades over the balls' surface, maximising oxygen transfer and creating ideal conditions for aerobic nitrifying bacteria. Because they do not compact or clog, they maintain consistent flow through the media bed over years of use. A 500ml bag fills a standard sump chamber segment and is sufficient for tanks up to 150 litres. Bio balls are most effective when used in the wet-dry (trickle) zone above the water line, where exposure to both air and water delivers maximum oxygenation.