We bought some yoyo loaches at the weekend. They all died. We also lost a couple of neon tetra and the loaches we replaced the dead loaches with are looking very ill and one has already died. One of the guppies is also ill. We're pretty novice fishkeepers, we cycled the tank and have been stocking it over the last few months. We haven't had any problems showing up in water tests although we have realised that our tank cleaning regime needs improving.
What can I do to treat the fish? The shops are shut, is there anything I can do to help them until then?
Will all of my other fish catch it?