My Queen Angelfish was a monster two days ago. She ripped up seaweed, swam great, and had awesome coloration. We added a phosphate remover to deal with a red algae problem, and after three days we added the algae killer (two days ago). We tested for ammonia, and the results came about .5 mg
/L. Did a 30% water change, and then we did another 30% water change. Turned the skimmer back on, and turned off the UV
Sterilizer because we purchased a bacteria additive to break down ammonia.
All of the sudden yesterday, she just wasn't swimming right. She jerked her head left and right when she tried to move. Sometimes, she came up to the surface and did what looked like spitting water. Then she started to just sit on the bottom. Her gills are still flowing, her coloration is still good, and none of the other fish are bothering her. She never scratched. Is there some sort of internal parasite that can infect a fish in a day? Could it be a stroke or something? This is our favorite fish and we are willing to do anything to keep her.