Pink algae is not an algae at all, but a bacteria. Normal algaecides will not reliably work on them. There are products that are designed to assist chlorine with removal of these bacteria. To eliminate pink algae, you must super chlorinate your pool, turn off the filter, and clean it with a good filter cleaner. Let the filter soak overnight then backwash to waste. Let the chlorine level subside before using again. (Hint: a good rule of thumb is to toss into the pool the equipment that is normally used for pool maintenance, including hoses, brushes, etc. prior to super chlorinating. These need to be disinfected too).