I woke up Christmas morning, after doing water changes of about 50% on my 100 and my 55 on Christmas eve, to find most of my fish dead or dying. In both tanks. My ammonia 0, nitrite 0, nitrate 0 on Christmas eve, woke up to dead and dying fish and my params off the friggin charts. I have no idea what happened. This has never happened to me before. I dosed with prime in my 100, and with prime and ferts in the 55. I have been treating my black neons for body fungus in my hospital tank. Today, I am still devastated. I lost 6 of 9 Cichlids in my 100, and it wiped out my guppies, I only have about 10 left. All three bn plecos are dead, I only have 5 of 11 black neons left, my albino cory died too. Seriously I have no idea what happened. I am really upset and freaking out that it is my water, so I put a call in to my water treatment facility and the city to see if something has changed, but they are so unhelpful. My husband wants to send water to a private lab to see what they find, because the only thing I did was water changes. My 100 has been up for a year+, my 100 for nearly a year and I have never lost fish like this. Even the ones I could save are in my hospital tanks, but they don't look great. I have 20 blue Briggs coming and 10 ivory briggs coming after new years that I bought on aquabid and I am ready to tell the seller not to send them. My plants in the 55 are doing fine. No discoloration or rot. Does anyone have any advice? I would really appreciate it. Thanks.:cry: