The water in the koi pond at Nelson’s is kept clear by an Island Bog. Taros and grasses are growing in gravel in the Island, while water is filtered through the gravel. The gravel is home to millions of tiny bacteria which break down the trapped organic matter (fish waste, and plant parts) into nutrients (fertilizer) which then feeds the plants. Sometimes we need to do a little grooming!
Picture #1 is the overgrown bog filter.
Picture #2 is Alex removing some of the fish food. Fish food? That looks like plant leaves to me! When fish food goes in the pond, the fish produce waste (poop) which is then turned into plants via the filter! Fish Food in, Plant tissue out!
The last picture is the trimmed up bog filter.
