Thank you for all your help.

It is a miracle. When I opened the pool yesterday, the water is pretty clear. I can see the bottom finally. I think the cover kept the chlorine in the water. Also, I have put in two chlorine stick in the two skimmers. That probably kept the chlorine level up. I put in 3 gallons of bleach yesterday and today to keep up the chlorine level. Hopefully, by the end of this week, I can use the pool. Thank you for all your advises. I really learnt a lot in this forum.

On the other hand, do you know what I found in the water after the water turns clear. I found a box level. Those mason people must have dropped that in the pool. I also found the head of the Polaris 150. The hose is detached from the Polaris 150 when it is operating. Since the water is so cloudy, I cannot locate the head until now. I do not like those cleaner that have to be attach to the skimmer. I have a DE filter. It always clog up the filter. I have since backwash for so many times.

I have bought the Dolphin Dynamics from Costco. I read all the posts warning people about the Dolphin cleaner. I wish to give it a try. It cleared all the dirt (seeds from spring and sand and even gravels.) from the bottom of the pool.