Freaked Out by ALgae Help!

[mysticgraces]

Hi Everyone..we are so newbies to the larger pool and we are freaked that we found some algae at the bottom yesterday...its not alot,just bits here and there on the bottom,but Iam freaked that it will get worst

When we had the water tested,we were told the chlorine was high,but the stabalizer and cal were low..

How can I get rid of the algae step by step.
Here are our stats

18X33 Oval above ground-64000 Liters
Sand filter

Free Chlorine-4.0
PH-7.5
Hardiness-`135
Alka-104
Cya-120

The pool place told us to add more cal and stabalizer

Thanks so so much!