Do not use anti-biotics unless you know what the problem is.

[GaryE]

I'll go as far as saying, "Don't use any meds" unless, if you want to put the infected fish in a separate tank with meds. Most diseases occur from lack of maintenance or an addition of a new fish to the tank, other than that, frequent water changes and not over feeding will let you have a healthy tank.

This makes sense if you quarantine. But an unquarantined fish that has already been in contact with your tank can be dripping Myco, leaking Camallanus eggs, etc. Remove a fish with ich, and you have two tanks with a large parasite load running loose in them.

If you put a carrier of a communicable bacterial disease, a parasite or a virus into a community, the community is rapidly infected. You've given your tank a disease dip if you simply move the affected fish out.

I got some tetras a while back that developed I don't know what. I lost a lot of them. This week, the survivors, months later showed the initial symptoms. No other fish was affected and it hadn't spread outside that group at all. So I sadly chose to euthanize those fish. I am now closely monitoring the other fish (bought at the same time, same source) for any symptoms. It may have been a species specific thing - I hadn't seen it before. There, I removed fish because they seemed to have kept the disease among themselves for several months.

 

[Alice B]

Quarantine is necessary. so is Maintenance. but I have a selection of fish meds to deal with the cornucopia of diseases the average pet store distributes widely, and usually know when to use them. Usually that is in quarantine, unless something hides in quarantine and gets in my community tank. Anymore I am just setting up species tanks, quarantine in them, and don't add more fish, I am very tired of spending a lot for sick fish. I kind of want a pair of dojo loaches to hang out with my tetras, and that will complete my fish. Just guppies and bristlenose in my 55. and plants.