Our pool is green and pool store says to replace sand

We had a lot of rain last week and our pool turned green. So two days later (Saturday) I added 5lbs of shock. It didn’t change color but I also didn’t do a lot of brushing that day. Monday I took a sample to the pool store. The test results were:
FC: 0.08
TC: 0.13
CC: 0.05
Ph: 7.5
Hardness: 363
Alkalinity: 46
Cya: 38
Copper 0.2
Iron 0.2
Phosphate: 0
Total dissolved solids: 500

they recommended 20lbs alkalinity
3lbs shock and 8oz algaezone

I backwashed the pool and then put all those in...

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