Sick Tiger Barbs

[3fsh]

I just bought 2 large and 6 small tiger barbs 3-4 days ago and added them to my 12G cycled tank. They looked fine when I purchased them, but I noticed some had small white spots on them and one of the larger ones had a red, swollen mouth. I went back to the lfs I got them from and noticed that the ones in the tank had the same problem. (Small white spots and red inflamed mouths--some had fungus growing on their mouths.) My water quality is superb, so I was really ticked when I found out that my tank now has some infectious thing in it. The guy at the store gave me some antibiotic medication, but the large fish with the messed up mouth died this morning. Also, the other large fish and one small fish have died. He said he would replace the fish with other tiger barbs, but I don't want any more sick fish. He also said he would take my fish back. This guy has been a real pain in the you-know-what so I'm wondering, should just return the fish or try to treat them?

 

[3fsh]

Also, I forgot to add something... hehehe... I have a 25G eclipse saltwater aquarium cycling with live sand, 10 pounds of live rock, and 1 picasso trigger. The guy at the lfs told me he would be great to cycle the tank with, but I don't know if I should trust him after what happened to my tiger barbs. (Plus, the picasso cost me 25$ and I REALLY don't want to waste my money on a fish that is going to die.) Should I sell the picasso and cycle with another fish?

 

[canarsie11]

Sounds like you tigers have mouth fungus.

They can recover, but it will be hard. Can pick your school of one by one. Instead of medication you should took the fish back.

 

[canarsie11]

Also examine the fish in the tanks at you lfs. Ask them what day they enter new stock, I got fish stores all the time keep an eye on their stock for atleast a week b4 purchase.

 

[3fsh]

I've decided to take them back today. How can I sterilize my tank without killing all of the beneficial bacteria?