Skimmers and phosphate?

[reefer31]

Do skimmers in a very small way remove phosphates from the water? In chemistry class today they were talking about how phosphorous is oxyphilic (i think thats the word). If that is right, phosphorous would want to be with oxygen. So, wouldnt the skimmer be able to remove phosphates too, by binding to the oxygen? Im probably way off on this but just a thought .

 

[bertoni]

Skimmer will remove organic compounds that otherwise could degrade into free phosphate. This article covers skimming in some detail:

http://reefkeeping.com/issues/2006-08/rhf/index.php

 

[reefer31]

I know that skimmers will take out DOC I was wondering if the already degraded compounds....phosphates, would be removed by the skimmer through the mechanism I described above or am I just dumb :/

Thanks for the link btw.

 

[reefer31]

Ahh..found my answer in your link ...

"In general, nitrite, nitrate and phosphate will not be directly skimmed out of seawater because they do not adsorb onto air water interfaces. Nitrogen and phosphorus are, however, readily removed as parts of organic molecules that are skimmed out. Analyses of skimmate, as mentioned above, are fairly limited in scope, but one published study shows a substantial elevation in total phosphorus (on the order of a thousand-fold) and total nitrogen (on the order of a hundred-fold) relative to ions not selectively skimmed out (say, magnesium or sodium) when compared to the ratio of the same ions in seawater or reef aquarium water."

 

[PharmrJohn]

Good thread. And you're not dumb. It was a valid question.

 

[Jk5]

Another interesting link...
"Gone with skimmer"

http://www.reefkeeping.com/issues/2002-12/rs/feature/index.php

http://forum.marinedepot.com/Topic52254-9-1.aspx?Highlight=skimmer+cup

 

[bertoni]

I should have been more precise. Phosphate is already oxidized, so it's not going to be oxyphilic. To be skimmed, the compounds need to be amphipathic, which means they have one or more water-soluble portions and one or more water-insoluble portions. It's the non-soluble parts that form a layer around the air surface of a bubble. Think of the insoluble parts as being "pushed" out of the water.

Phosphate is highly soluble, so it's not going to go to the surface.

 

[redfishsc]

I think this is part of the reason that dosing vodka/vinegar/sugar (or other carbon types) help remove phosphate and nitrate so well.


The bacteria consume the nitrate and phosphate, thereby taking the inorganic forms of phosphate and making them organic (ie, in the bacteria). Then the bacteria and resulting "scum" is skimmed out of the tank.

Kinda like trying to clean up iron filings or nails or whatever; a pain in the but to remove but you can trap them all with a magnet and get rid of them all at once.