i'm new to pool ownership, so i'm an amateur compared to the experienced pool guy recommended to me by my pool contractor. i figure it's worth watching him do things for a while before i think i'm smart enough to take over.
he taught me to preshock before bad weather to keep up with chlorine demand.
he found a leak at the water temperature sensor insertion point where i would have never thought to look. the leak occurred because the installation workers tightened the clamp holding the temp sensor too much and it permanently flattened the pipe and temp sensor's O-ring. the pool contractor replaced both pipe and O-ring.
unfortunately, he didn't see that the water feature pump was way too big. a 2 1/2 hp water pump was installed instead of a much smaller pump; my pool pump is only 2 hp! the contractor's employee discovered this when they were installing the water feature, which was much later than when the equipment was installed.
so why did i hire a pool guy? training and experience, Grasshopper.