Swimming Pool Skimmers draw water in similar to the main drain, the difference is they only suck water from the very top of the pool. As your pool pump circulates the water, it stirs the pool water around, the debris that floats to the top layer; leaves, suntan oil, and hair are pulled in and end up in your skimmer basket. Simmers usually have a square opening with a floating, flap-like door called a weir. The weir keeps the debris that has entered the skimmer from re-entering the swimming pool, and collects in your pool skimmer basket.
The skimmers internal parts need to remain in good working order and the basket emptied regularly to help keep your pool water circulating. A full skimmer basket dams up your return to your filter and impacts circulation. Circulation is needed to keep your pool water healthy. If your pool is older and does not have a skimmer, you can add a floating skimmer which attaches to the suction line with a hose. A floating skimmer gives you the benefits of having a skimmer without any renovation. Since this will drift throughout your pools surface, it is recommended you remove the floating skimmer before swimmers enter, to prevent young children from getting tangled up in the hose.