Is your tank filtered and heated? How long has it been set - up and what are the readings on ammonia, nitrite, and nitrate in the water? What do you dechlorinate the water with and what do you have in the tank besides the minnow (fish, plants) Do you use any other chemicals in the tank? How often do you change the water and how much do you change each time and how large is the tank? These questions will really help us to help you if you can answer them. If you have removed the fish from the tank and put it in another container with fresh dechlorinated water and it is acting better, please let us know.
If you have not removed the fish from the tank and put it in fresh dechlorinated water, please do so.
That type of behavior is almost always an indication that there is something in the water that is distressing the fish. Do you have a Test Kit to get the actual test readings for AMMONIA, NITRITES, and NITRATES? We really need to know the readings, not just an OK.
The problem might even be in the tap water. Are you using a product to take the chlorine out of the tap water? If so what?
I really need to have answers to the questions that I asked before.
Okay so you test the water. How much are the levels of Ammonia? of Nitrite? of Nitrate? I need the numbers of the test results, Please.
I do not know what to tell you as you are not giving me enough information. Are you running an airstone to keep a lot of oxygen in the water and what is the temperature. Can you please answer some of my questions? I know you are upset and it is hard but I need you to concentrate and give me some answers if I am to help you.
its got gill/skin fluke! its a little parasite that effects the skin and gills (obviously) one of my danios had it so I put some meds in ther called methylene blue, it works a treat. although its dye based so it does turn the water blue but that clears with a carbon pad. hope this helps