I was running phosban and then phosar through a cannister filter. When I would replace the media, I noticed that the water always made "tunnels" through it, therefore limiting the contact the water had with ALL the media.
I got a phosban reactor and it definitely works like Christy said...with the water coming into contact with all the media. I'm a fan.
(As a side note, and not to hijack, but would it be problematic to put a little phosban and a little carbon in the same reactor? I hope not because I already did...lol.
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