The dirty pond water is first passed through a pre-filter bag, so that leaves, algae, sticks and stones etc are collected. The filter bag can be easily removed and opened for cleaning. If you do not wish to waste the water, it can be connected to an external pond filter (e.g. sieve filter, drum filter or fleece filter) to be recycled back to the pond, using the connector which takes 32/38mm standard pond flexi hose.
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