I don't know whether it is bacteria or algae, but it seems to be a common complaint with Baquacil pools that are a few years old. I don't know what to tell you, except to convert it to chlorine. Don't know how many weeks of swimming you have left, but if you'll go to the Baq forum and read through the posts there, you'll see that most of the people there who have converted have done so in about a week's time--you could still salvage some of the swim season.

Welcome to the forum!

Janet