You should check your pool chemistry once or twice a week during the summer and once every week or two in the winter. The pH should be kept between 7.2 and 7.8, the lower the pH on this scale the less chlorine your pool will need. As pH rises, chlorine starts becoming less and less active therefor many consumers just keep adding it. Chlorine at 7.0 pH id about 50 percent active and at 8.0 is about 10 percent active. Control pH properly and you will need and use much less chlorine.

The skimmer is installed in the side of the pool, and its primary job is to skim the surface of the pool before debris and contaminants become saturated and float down to the bottom of the pool. Everything in your pool enters at the surface of the water, the effective the skimmer is, the more stuff it can skim off the pool the better. There is a round access panel on your deck; open it up and dump the contents of the basket as needed. Keep it cleaned out at all times.  

You should do this every couple of weeks or as needed. Turn off the pump to do this and release pressure on the system. This is the basket installed just inside the clear glass of your swimming pool pump. Or, you can clean out the debris catcher or leaf basket. A leaf trapper and a debris removal system is recommended. Get a variable speed or 2-speed pump sooner than later if you have not upgraded already. Multi-speed pumps are worth the initial expense.

Is it too high or too low? Your water needs to be right at the center level of your pool skimmer or pool tile for optimal results and performance. If it is low, it can run the pump dry and burn it up, or if too high, the skimmer door will not work properly. That door keeps the debris in the skimmer.