The surface skimmer provides a permanently clean water surface, reducing oily film residue and therefore contributing to a reduction of microorganisms, better oxygen exchange and greater light penetration. It skims off the film residue and constantly brings new layers of water to the surface.
The film residue is an unsightly film on the water surface of the aquarium Organic material like fats, proteins and waste matter gather here, forming a feeding ground for a host of unwanted microorganisms. The surface is, however, necessary for the essential oxygen exchange between the water and air. A film on the water surface reduces both the rate of diffusion and, on the other hand, the on-going biological surface processes also needed for extra oxygen. Light penetration will also be reduced and consequently plant growth as well as photosynthesis will be compromised.