Really need pool shocking advice
My pool is green and I need a plan to quickly, inexpensively make it look OK when a prospective buyer is coming! Unfortunately I do not have the time and money to properly get rid of all the algae and debris. I just want it to look blueish and so-so when a buyer comes by. It can look cloudy with dead algae and debris at the bottom.
From past experience with the pool, I believe I can add chlorine to shock levels, brush the pool once, and keep adding chlorine as long as I can. Preferrably 48 hours and preferrably brush the pool a second time, but again I am short on time.
After I shock it initally, I plan to bring it to shock levels every week if I can, but especially the day before someone comes to look. I am in a difficult situation and need to just make it look OK on the cheap. I have a vinyl liner which I don't want to ruin, but I am not worried about making it good enough to swim.
My question is about the CYA, TA, and other chemical levels I need to worry about. I don't fully understand and wanted to verify. I think I understand pH but not the others. My plan is to lower the pH to 7.0 every time before I shock. After I shock I believe the pH will go up on its own. Does the rain also cause pH to go up if inches get in the pool? I thought this was a problem.
With CYA I know the chlorine I add goes farther if I have a low CYA. However doesn't the low CYA cause me trouble after I shock, it makes the chlorine less stable so it breaks down faster in the sunlight? So should I go ahead and do 30ppm CYA now before shocking the first time, or only start adding it after the first major shock? I do not know my current CYA but I'm assuming 20-30. It might be less and certainly not more. I am not sure I can cover the pool in between every viewer, so it may get a lot of sunlight. I believe it helps save money on chlorine if I can block a lot of sunlight.
All I know how to do is raise CYA and TA when needed, lower pH as needed, and add the chlorine (raising pH goes with it). For TA do I need to do anything besides make sure it doesn't go below 80 or above 120? I'm pretty sure my TA is always low, same with my CYA, so I never worried about lowering them. I seem to have problems with keeping my TA up due to always adding shock chlorine and raising pH. Also I hate to use so much pH lowering acid. Last year I kept running in these 2 problems and maybe other problems. I was confused and still am, because of how one can affect the other. What else do I need to worry about or learn about?