fish look sick........

Question
I have a ?100 gal. goldfish pond, outside, but in a screened in enclosure.  I have 6 goldfish.  They look lethargic and a have a milky coating all over and their fins look ruffled.  I have a pump in the pond.  What could it be?

Answer
Hi Becky;

Get a sample of the pond water and have it tested at the local fish store. Test the ammonia, nitrite, nitrate and pH.

Ammonia and nitrite should always be at "zero". If they are elevated your fish will show the signs you described because it burns their gills and skin. Water changes are the only way to bring them down and make the water safer for your fish. Both ammonia and nitrite are natural toxins that should be consumed by beneficial bacteria that lives in the filter. If the filter is new or has been recently cleaned, this bacteria will not be prevalent enough to consume the toxins.

PH should be in the range of 6.8 to 7.8. If it is too low or too high the fish will exhibit the symptoms you describe.

Nitrate should be no higher than 40 ppm. If too high the fish will get sick easily. It is fairly low in toxicity, that's why some is okay. Make regular water changes of 25% every week to keep it low. Live plants use nitrate for food, so outdoor ponds with plants and algae usually have lower levels of nitrate.

Let me know what the readings of the tests are. If they seem normal, the fish will need treatment for bacterial infection and/or parasites. Look at your local fish store for pond medications and read the labels to see if your fishes' symptoms are described on any of them to treat it. Don't use the medicine without testing the water first. If the cause of their suffering is a water quality issue they will get worse with the addition of medicine. To help the fish right away, change 25% of the water. Use a good water conditioner when adding the correct temperature of fresh water back. No matter what the problem is it will make them feel better until we can figure out what is going on.

Let me know as soon as you can about the tests.....

Chris Robbins