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. PT1736 - Pressure Flo Foam Set (4pk) is suitable for the following Laguna models: Laguna Pressure Flo 5000 Laguna Pressure Flo 6000 Laguna Pressure Flo 7500.
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