Getting a late start. trying to open the pool and cannot get rid of green dark algae.
Total hardness 250
total chlorine 3ppm
Free chlorine 3ppm
PH 7.0 Raising a little at a time with borax
Total alkalinity 20 ppm
sanitizer 10ppm not wanting to add sanitizer having to backwash too often thought it would be a waste
the pool is 22,000 gallon on ground pool with 8 foot deep end
any suggestions would be greatly appreciated

Thank,Tim