Build-in Air Stone Build-in air stone helps with aeration and circulation of nutrition to your hydroponic system. L-connector to Air Pump Connect to the air pump, suitable for 4mm/0.16in air tube Easy to Set Up Please squeeze the sponge repeatedly until the sponge is full of water, so that the filter can sink on the bottom of the aquarium. 24 Hours Efficient Filtration The sponge filter provides mechanical filtration, with vertical pattern design, increasing the filtering area and helping to filter efficiently; Bio ceramic media balls provide biological filtration, it helps with decomposing harmful substances and cultivating beneficial nitrifying bacterial at the same time.
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