Stupid question. Why can’t I dose this?

[Miami Reef]

I rinsed my GFO in my reactor by running it into a container until it turned clear.

Hypothetically speaking, why can’t a person just dose this iron to the tank? Would the iron go too high?

This question is mainly as a theoretical question. I’m a curious person.

If this question sounds too silly, let’s assume I only add the brown liquid (not the solid particles on the bottom).

 

[Rtaylor]

Iron consists of heavy metals. Heavy metals accumulate in tissue. You (and I assume fish) can get iron poisoning if you ingest too much.

 

[elysics]

So you have a sludge of unknown purity, unknown concentration, the fact that out is a sludge and not a solution, no idea of it is the right chemical form...

Remedying all of those is probably more effort than just buying the proper chemical/solution. It's iron, it's not particularly expensive and you don't need much.

 

[sjfishguy]

Ferric oxide (aka rust, aka GFO) is not very soluble in water. Ferric chloride and ferric nitrate, etc are solvable iron salts and would be used to dose (if you wanted)

 

[taricha]

Like others have said, fine particles of GFO are particulate Fe, not soluble.
In other words the water itself would have very little bioavailable Fe in it. The solids would settle into the sand and may be difficult to ever remove.

 

[Randy Holmes-Farley Verified Community Expert]

I think it is likely GFO does add some soluble iron as organics strip away some iron from the surface, and some may just pop off. IMO, this released iron is a likely or at least a part of the reason some folks see deposition of CaCO3 downstream of GFI because iron is known to help nucleate calcium carbonate precipitates.

 

[FishTruck]

very fine stuff, like tumbled carbon and maybe GFO, can get loose in the system and coat the corals like dust. I usually let it go into a filter sock after the reactor to prevent this. I