Why do we need to use protein skimmer

[diverxxx]

A protein skimmer used to remove unwanted organics such as food and waste particles. It is most commonly used in commercial applications like municipal water treatment facilities & public aquariums. Smaller protein skimmers are also used for filtration of home aquariums.

Protein skimming removes certain organic compounds, including proteins and amino acid found in food particles. These molecules are called amphiphatic or amphiphilic. Commercial protein skimmers work by generating a large air/water interface, specifically by injecting large numbers of bubbles into the water column. In general, the smaller the bubbles the more effective the protein skimming is because the surface area of small bubbles occupying the same volume is much greater than the same volume of larger bubble. This is very important as these amphipathic organic molecules will begin to collect on the bubble surface.

So what's are the ingredient to make up that greenish yellow soup?

there are a number of other organic and inorganic molecules that are typically removed. These include a variety of fats, fatty acids, carbohydrates, metals such as copper and trace elements such as iodine

Alternative forms of skimmer have recently come into use, including the algae scrubber, which leaves food particles in the water for corals and small fish to consume, but removes the noxious compounds including ammonia, nitrite, nitrate, and phosphate that protein skimmers do not remove.

[blusafe]

I see you trolling around the forums posting what seems to be newbie advice. You should considering referencing your sources, unless of course you figured out all this information on your own. You forgot to discuss saltwater surface tension is much higher than freshwater (which is why skimmers don't work for fw).

[artxakis]

l read what he wrote on advanced aquarist before. i think that article stated the amount of gunk removed from protein skimmer is not as much as using carbon filtration but i think protein skimmer is still king for filtration.

[liquidnoise]

so is wet skim better or dryer better?

[tofubox]

I prefer to keep mine in between, leaning more to the dry side.

From my understanding, dry skim = maximising organic impurity per unit volume of foam, (u get the most of what is extracted from the foam). Wet skim = Overall increased efficiency of removal of organic impurities. (U get maximum extraction with additional foam, lesser organic impurity per unit vol, but vol of extraction is increased)

Plenty of articles to read, but thats what i came to conclude. Both works well. Individual preference.