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GFO & Phosphate Removal

GFO, like Phosban, is a delicate rust colored media that strips phosphate from the water. Without phosphate, green hair algae and other nuisance algae will starve. GFO will clump and not work properly if placed in a filter media bag. For best results, use a media reactor with a low flow pump to gently fluidize and tumble the media. Don’t overfill the reactor. Before placing the media in the reactor, rinse GFO with purified water. Replace GFO as needed, about every 4-6 weeks. A digital phosphate test kit, like the Hanna phosphate checker, will let you know when to change the media.

We also carry other types of phosphate removal media that can be placed in a sump or traditional filter.


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