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Be sure you at least rinse the filters. As it comes loose from surfaces and plumbing, it will end up in the filters, and if it's not dead, it will begin the process again. I tell folks to rinse the filters out for a few days after they feel they have killed it all, just to be sure.And I would LOVE to know where it comes from: I can go a year without hearing about it, and then we will have ten customers come in the same weekend asking about it, from different parts of town.
Would soaking the filters in a bleach water solution for few hours be a good idea in that case?