What are the tiny yellowish bugs that fly around pool water and bite and how do you get rid of them?

Getting bugs out of a pool can bug ya, pun intended. No mention of what type of bug you are talking about. There are two basic types 1-on top of the water and 2-under the water. The type on top of the water can be removed using an algaecide that is a quantanary ammonium compound. This chemical makes the water wetter, sounds crazy but these bugs ride on an air pocket on their belly and this algaecide will take that air pocket away and they will drown in the pool water. If you use a salt generator you don't want to use this chemical use a polymeric algaecide of at least 60%. The under the water bug known as a water bug can be killed by shock treating the pool with Calcium Hypo Chlorite at of at least 65%. You cannot use this product if you are using an ionizer or a non-chlorine based system. you are most likely refering to boatmen. About the only ways to keep them out is to keep your PH balanced and your chlorine level around 4-5.0. There is also a bug out product called t-san made in Salt Lake City Utah which helps eliminate boatmen and is safe in and around pool & people.

empty out the pool and then refull it with clean water