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Seachem Phosguard (and aluminum oxide phosphate removers)


Mar 10, 2020
Has anyone used Phosguard in their octopus tanks? I've used GFO (granular ferric oxide) in my system without any apparent octopus health issues, and have some Seachem Phosguard that uses aluminum oxide to absorb the phosphate, but can't find anything about whether or not it's octopus safe. Supposedly Seachem's doesn't leak aluminum into the water like some older aluminum oxide phosphate removers do - Seachem often advertises that all their stuff is safe for all sorts of reef tanks, but I saw that their Flourish algae supplement has small amounts of copper in it so, I'm skeptical. GFO (Ferric oxide) is also metal based (which makes me nervous), so if anyone has info about using that with octopus, that would be useful too.

GFO should be okay to use in your octopus system. I use PURA Phoslock in my systems and have never had any negative effects. If you are really concerned about leeching metals into your system, you can also add some cuproisorb to pull out any heavy metals in your system. I think this stuff I linked changes color when it comes in contact with copper so you will be able to see if your phosphate remover is leeching anything nasty into the system.

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