Does My Goldfish Have a Parasite?

Hello. My goldfish is 12 years old and last week I changed half the water in the tank after a clean out.

I didn't put enough water treatment in the water and the fish got pH shock. It was in shock for four hours then I realised and treated the water.

After another four hours the fish was back to normal. I then went on holiday the next day for a week and left it with lots of fresh plants as I normally do.

I came back from holiday yesterday and have noticed my fish is displaying some signs of a parasite. It is occasionally rubbing against stones (which it has never done before), swimming erratically, breathing fast and deeply, some scales have turned white, it's eyes have bulged slightly and the fresh plant has turned slightly brown and most of it has been eaten.

However there is no clear parasite, like white spot, anywhere in the tank. My question is should I treat it with a parasite medication even though I am not sure that is what it has?

Any advice would be great! Thank you.

Vicky.

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Grant's Reply

Hi Vicky

There are two possibilities here, parasites have been introduced with the weed, or the pH shock has caused skin and gill damage.

Was it pH shock or chlorine burn?

Chlorine burn damages gills and skin, causing the symptoms you are describing.

Put the fish into a mild salt bath of two teaspoons of un-iodized salt per gallon immediately, ensuring good aeration to keep oxygen levels high.

Treat the water with something like Stress Coat to help with skin repair.

That is about all you can do for Chlorine burn or pH shock.

Let us assume there is also a parasite problem, (which may have been brought on by the skin being damaged).

It will be one of two groups. The first could be flukes, worms or protozoan parasites, the second anchor worm or lice.

I've grouped them like this because of the treatment methods.

Check out the anchor worm and lice pages to see if your fish has either of these. Both are treated the same way as they are both fresh water crustaceans. These are commonly introduced into an aquarium or pond on plants sourced from natural waterways.

If you can eliminate these parasites, then it has to be one of the first group. These are harder to identify, but this group of parasites can be treated with a Praziquantel based medication.

You will need to act fairly quickly because protozoan parasites can destroy the gills.