Hi all, Ive just been over inspecting my fish in the Guppy, Rosy barb and White cloud tank because i have a 6 month old guppy that i think is pregnant but that's another matter. Something has happened in the last 5 hours, there is a big red mark on my baby guppies cheek and behind her swimming fin. The water in that tank was tested 5 hours ago with readings of: pH 7.6 Ammonia 0 Nitrite 0 Nitrate 10 Here she is: Do you think she has been bitten by a Rosy barb? Or is it something else? This mark was not there 5 hours ago.