I am a first time bromine user. This is actually my first pool (helped my parents take care of their above ground chlorine pool). I just moved into a house with a 28,000 gallon in ground pool. I just had the liner replaced because it was about 11 years old and coming off the wall. The original pool was sanitized with bromine and the owners had several buckets left over so I figured I would just continue to use bromine (just recently read that once a bromine pool always a bromine pool so maybe a bad mistake!) I am using a Rainbow 320 feeder (feeding from the top port). All my levels (hardness, alkalinity, and pH) are right on the mark. However, I cannot get my bromine levels up. The feeder is at the maximum setting and my total bromine is basically 0 ppm. I bought 4 lbs of bromine booster and put them in yesterday but still reading 0 ppm. I've been using chlorine granular shock to try to bring the levels up (my pool place recommended this) but still 0. The water looks great, however, I am concerned about why I cannot get my sanitizer level right. Any help for this newbie would be great. How can I get my levels up? Is it still to late to switch to chlorine as my sanitizer?