In the interest of gathering information as well as encouraging lively and constructive debate, I'm launching a series of discussions about specific topics where either no consensus exists or where misinformation, disinformation or conflicting information frequently occurs. This week's topic: Do wetting agents like Kodak Photo Flo or equivalents from other manufacturers contaminate reels and tanks? Specifically, over the years I've heard numerous claims that wetting agents can contaminate or leave a tenacious residue on plastic reels. Personally, I'm skeptical of the claim. I've even begun to delete unsubstantiated claims of this type, in the interest of avoiding confusion for those who are new to the b&w darkroom. But I could be wrong. While I welcome your opinions and anecdotal observations, I'm hoping as well to see some substantiation, some hard evidence that has isolated the problem to wetting agents. I suspect that contaminated, stained or gummy reels are due to other factors. But for the sake of gathering information, let's open this topic to discussion. And if I've chastised anyone before on the forum or deleted your claims, please rest assured that your constructively worded and relevant comments are welcome on this discussion. My only request is to keep remarks strictly relevant to this specific topic. If you have suggestions for other topics in this series, please e-mail me off-forum by clicking on my name and following the prompts. Thanks. I'm hoping this will be a welcome relief to those who tolerated the recent off-topic digressions and unpleasantness.