NT Labs Aquarium KH Up - PH Stabiliser. These high quality, super absorbent foams are custom designed to fit inside the Laguna Pressure-Flo Filters making them very easy to install. PT1735 - Pressure Flo Foam Set (3pk) is suitable for the following Laguna models: Laguna Pressure Flo 2500 Laguna Pressure Flo 3000 Laguna Pressure Flo 4000.
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