What useful things does GFO deplete

[LadyTang2]

We all know GFO can be useful to reduce phos, but what are some desirable compounds/elements/anything that GFO might reduce?

This is from one of Randy's articles about what might be being depleted "including trace metals, arsenic, selenium,2 silicate, and organics. Metals such as manganese, cobalt, nickel, and zinc are known to bind to iron oxide hydroxide in simulated seawater solutions."

Which of these are most useful and depleted by GFO, others? Does it make sense to dose any of those things it depletes or should one just do ICP and dose accordingly

 

[rkpetersen]

Also binds copper pretty dramatically.
If you're using GFO, it's not a bad idea to add a trace element mix to your system once or twice a week.