topless,

According to the Best Guess table, for your level of CYA (150 ppm according to your first post) you need to get the chlorine to 25 ppm to shock. You'll need to keep it at that level until the algae is gone and the water will keep the same level of free chlorine overnight.

Testing several times a day and adding bleach to return the chlorine to shock level will give you the best results. At a minimum, test and chlorinate in the morning and evening but three times a day will probably get this problem cleared up more quickly.

Best of luck.