Hi everyone, I have an emergency on my hands and I don't know what to do. My 50 gal has been running for two months. Parameters: Ammonia: 2.0 Nitrites: 0 Nitrates: 2ish? (definitely not 0, as it is not pure yellow, but also not 5 because it isn't bright orange) I'm not sure what's going on. I know I threw my parameters out of whack because I recently changed filter systems and ended up causing a new mini cycle in the process. I've been doing frequent 40% water changes (twice a week), and dosing with stability and prime daily. Everyone has been healthy and active, but just now I found one of my fancy guppies up near the surface gasping, with red gills flaring out. He struggled with ich when I first got him, and never fully recovered as he still looks ragged and never grew his tail back the way the others who had it did. I'm worried that he's too weak to handle the ammonia spike, but I have a molly with popeye in my quarantine tank and it's dosed with Maracyn, so I'm not sure if I should move him there. What do I do?!?! He's the only one showing any signs of distress. Although I did lose one endler last week, shortly after changing the filter system. It had ich as well (they were together when it broke out in a 10 gal). Any advice would be greatly appreciated!