my fish have been attacked

Question
Hi there,

Very stupidly the guy in the petshop sold us two crayfish and they have subsequently attacked two of my goldfish. We asked him whether they would be compatible and he said yes no problem, I'm annoyed but thats another matter.

We have now removed the crayfish from the tank, but I was wondering what I could do to help the two goldfish that have been attacked, one appears to be coping quite well with it's damaged fins but the other seems to be sticking to one spot, not moving much, he also appears to be the worst off, there is a slight cut just above where the tail is, he has pretty much lost all of it's tail.

Can you recomend anything what we should do? I don't him to die, and i would like to help the other one too.  

I have 4 other fish in the tank with them.

Answer
Hi Angelmouse;

Poor guys! Let's see what we can do to get them on the road to recovery;

Start by making a 25% water change. Do them every other day for a week to keep the water especially clean and help avoid infection. Also add a little aquarium salt. Your tank needs 1/2 teaspoon per gallon. Every time you make those 25% water changes, add more salt for the water replaced. For instance, if you remove two gallons of water add back 1 teaspoon of aquarium salt with the fresh water to replenish it again. The salt helps fight infection and gives back electrolytes to the fish that they lose when they're stressed.

While you are the fish store getting the salt look for a product called Melafix. It is natural and aids in fin and tissue regrowth by soothing the injured areas and preventing infection. Always avoid antibiotics and chemicals whenever possible. The only exception is a water conditioner. There are chemicals in it but they are actually helpful because they are removing other chemicals from tap water that could kill your fish. (Almost sounds weird, but it works)

Hope your guys feel better soon.....

At Your Service;
Chris Robbins

Come on over and join us on the freshwater fish forum at About.com to get even more information too;
http://freshaquarium.about.com/od/questionsanswers/a/naavigateforum.htm