UltraZap gravity filters are biological filter chambers that run on gravity flow — no pump or power required. The media inside hosts beneficial bacteria that convert toxic ammonia and nitrite into safer nitrates, keeping water balanced around the clock.

Four sizes cover everything from a small pond or large aquarium to a serious koi and fish-tank setup; pick the volume to match your flow.

Good to know:
– Four sizes: 15L, 25L, 50L and 100L
– Gravity-fed — no electricity needed
– Converts ammonia and nitrite to safer nitrates
– Choose the size to match your pond’s flow