Please someone help me I have a 60l aquarium that is a mess, a desaster, I had a female guppy that was doing white stringy poo but I didn't knew what it was and she died, then after giving birth 2 of the other guppys were doing that poo and they had sunken belly, so I searched and found out that it was a parasite, then I started to give them Esha Hexamita in a separate tank cuz supposedly it cures it, then my female swordtail started to have in the main tank too then I gave to the main tank the medicine, then in a space of one hour in the next day a Kuhli died another guppy female and a Molly in one moment she was eating like crazy almost fighting for food then I go back 1 hour after and she is in the bottom not moving and in a space of 4 min she died, I don't know if it is something wrong with the medicine, I am giving the right dosage, my tank has no amónia and no nitrite and nitrate 15ppm in a space of 1 week this happened.