Do you not keep notes as you do experiments? * tap water---control failed * bottled water (generic store brand)---control failed * distilled water-

Do you not keep notes as you do experiments? * tap water---control failed * bottled water (generic store brand)---control failed * distilled water---control succeeded and then when writing up the experiment, mention the use of distilled water? You might not be interested in why only distilled water worked, but someone else reading the paper might think to investigate.