Hi:
First thing is get some good test numbers for us--you can take a water sample to a pool store and have them test it--don't buy anythng yet, just get the results.

Here's what we need to see:

FC (Free Chlorine--the good stuff)
CC (Combined Chloramines--used up chlorine)
pH
TA (Total Alkalinity/Alkalinity or T/A)
Ca (Calcium or Calcium Hardness)
CYA (Cyanuric Acid/Stabilizer/Conditioner)

Also, if they can test for metals then that's good too--Copper (Cu), Iron (Fe), Silver(forgot the symbol).

Tests I couldn't care less about:
Acid Demand
Base Demand
Total Dissolved Solids
SI

If it's not copper making your water green, it's algae. Once you know it's algae (Cu is VERY low) you can add 3 gallons of regular bleach (5.25%) or 10 quarts of Ultra Bleach (6%). I would just pour it in the skimmer with the filter running.

But that's just a start--we'll need the other numbers.

If the green is from copper, the bleach will be the wrong thing to do.

If it is algae, do NOT add algaecides--bleach/liquid chlorine is the BEST algaecide.