What type of filtration is this?

[Nanoreefjoe]

http://www.amazon.com/gp/aw/d/B004SISTC6/ref=ox_sc_act_image_1?ie=UTF8&psc=1&smid=ATVPDKIKX0DER

 

Mechanical chemical biological?

[VW_TDI_02]

Yup. It's used in the Aqueon QuietFlow line and would be considered chemical and mechanical filtration. Inside of the filter floss there is a small amount of carbon which helps but I can't imagine that such a small amount of carbon will last very long. I have some of those that I use to get medication out of my freshwater tanks and there is maybe a tablespoon worth of carbon in there. Not really sure the quality of the carbon either.

 

As KEVENO said, if you leave it in long enough then it will start to develop bacteria and would be a source of biological filtration. This is typically not recommended because you aren't doing any sort of nutrient export. The detritus and food is being converted to nitrite and then nitrate which builds up in the water. It's recommended that you replace your mechanical filtration regularly in order to prevent this. This way, you are removing the detritus and food before it gets converted and starts polluting your water. Since those are quite expensive and should be replaced relatively often, I would recommend against using them unless budget isn't an issue. Most people tend to use filter floss because it is cheap and can be easily swapped in and out.