Okay so about a half a year ago I bought a plain yellow female guppy. She was a mature adult, so she was maybe 1 year old. SHe did fine and had 2 batches of fry until about 3 weeks ago when her gills turned light pink. Now she only moves to breath and just floats at the top where the bubbles can support her. I use freshwater salts (if you haven't heard of them it's like marine salt but in much lower doses and has freshwater electrolytes), WARDLEY 3 in 1 water conditioner for PH, ammonia, and Chlorines/Chloramines, I also have a Whisper Internal power filter with a biobag, and I use AquaSafe, it helps to enhance the slime coating on fish, and cleans out harmful metals in tank. My PH levels are around 7.2 to 7.5 (slightly alkaline for my livebearers. I am out of my ammoia test fluid so I can't give you that. Oh and the tank has The fish i am talking about, two colorless 3-month old baby guppies, 3 young male fancy guppies, 1 Algae eater (thats what they called it at LFS), and 1 young female guppy. Please help me!