View Full Version : Gfo vs Phosban

06/04/2014, 09:55 AM
My lfs swears by Phosban but I currently use brs hc gfo on a reactor. He says the Phosban is much more effective at eliminating specifically po4 where as gfo is not. I thought they were basicly the same thing. Can someone please explain? Thanks

Randy Holmes-Farley
06/04/2014, 10:56 AM
Phosban is just a particular name brand of GFO. There are many of them. :)

06/04/2014, 08:03 PM
They said GFO is not good at specifically removing phosphate? You'd better not get the phosban then, considering phosban = gfo.

Randy Holmes-Farley
06/05/2014, 04:44 AM
Just to be clear you understand the sarcasm, phosban is not more effective or more specific than other brands of GFO, including the bulk sold by BRS, Rowaphos brand, and others. :)

GFO will bind silicate and possibly some organics. I don't think there is any other binding to worry about, although all might cause a bit of calcium carbonate precipitation downstream of it due to released iron.

Some people also think it contributes to dinos, but many people, myself included, have used it for many years with no dino problem.

I discuss GFO in great detail here:

Iron Oxide Hydroxide (GFO) Phosphate Binders

06/05/2014, 11:26 AM
I recently switched from Phosban to BRS bulk GFO (not the high capacity stuff) and it seems the BRS GFO doesn't get ground up anywhere near as easily as the Phosban did.

Other than that, read Randy's link above. In fact, read every Dr. Randy Holmes-Farley article you can. Not only does he know what he's talking about, turns out he's really good at explaining it to chemistry inept idiots such as myself. :wildone:

06/05/2014, 02:39 PM
I have also used gfo for years without dinoflagellates. I've seen them pop up in friend's tanks with no gfo in play as well. For me BRS HC gfo has worked very well in the years I've used it. Low dust ; doesn't grind up ;tolerates regeneration well.

06/05/2014, 10:07 PM
Thanks for all the info and the great article on phosphate.

Randy Holmes-Farley
06/06/2014, 05:22 AM

Happy Reefing. :)