Mysterywriter221

Hi, I'm new here. My fish have recently survived an ick infection and now two of my goldfish have black spots on them.

One fish has a small amount of spotting on it's head and body.

The other one has heavy spotting on it's head, spines in the dorsal fin, and body.

Neither have any swelling under the spots or thickening of the scales. They are both swimming and eating regularly. They also swim in a school with the other fish in the tank.

Any help would be greatly appreciated!

Mysterywriter221

Uh-oh, I just noticed that the black spots are on another fish. Once again on the head and body and now on the tail.

Chief_waterchanger

Hi, and welcome to Fishlore and I hope to help you out on your fishkeeping.

First: When it comes to fishkeeping there are certain fish that can be kept with others and certain fish that should not be kept with certain other fish. Goldfish are what is called 'temperate' water fish. That means that goldfish tend to like cooler temperatures than tropical fish do. Temperate and tropical refer to climate zones, as you may have noticed.

Second: Goldfish should not be kept in small tanks (under 40-55g tanks) because they have a huge 'bioload' as compaired to a lot of other commonly kept fish. 'Bioload' is referring to the amount of waste excreted. The bioload is what is being considered when figuring out just how many of each fish should be kept in a tank without "overstocking" the tank. Very very few fishkeepers provide the space the fish would have in the wild, so we have to make do with what we can provide them, but there are minimal limits as to what the fish would do well in.

Third: The 'large algae eatter' you refer to, do you know what sort of algae eatter that is? There are plecostomus, otocinculus, as well as others that are commonly called 'algae eatters'.

Fourth: Most things sold in the fishkeeping hobby that are referred to as algae eatters are not compatable with goldfish due to differing temperature needs. Some people bring up that goldfish can "tolerate" tropical temperatures, and that is only sort of correct... They can survive in them, but it DRASTICALLY shortens their lifespans as well as opens them up to a whole list of diseases and disorders due to a weakened immune system.

I am going to research the black spots with my colleague and co-owner of our fishhouse who has a biology degree. I will post again as soon as we know more.

Mysterywriter221

I actually don't know what species my algea eater is. The store I bought him from simply had him labeled as an algea eater. I've had him about a year. He has always been fine with my goldfish.

My oldest fish is a goldfish named Sushi. He is about 2 years old. Sushi doesn't have the black spots.

The black spots are only on the fish I have had for about 6 months. They are the smallest in the tank. The largest two goldfish (Sushi and Shashimi) and my algea eater (Dickens) are unaffected so far.

Dickens is 10 inches long and black with some white spotting.

My tank is 30 gallons.

Thanks!

Mysterywriter221

I have always catered to the needs of my goldfish since there are more of them. I have never had a problem with Dickens. He was even unaffected by the ick.

Chief_waterchanger

With the ones having blackspots show up being so young I would say it is more than likely (I would attribute 90% likelyhood) that it is natural color changing that will continue to occur in most goldfish for 2-3 years of life or more.

I'm glad your fish are doing well. I hope you do not take my suggestions as being critical of your methods, because I definately do not mean to any bad critisism. The fish you describe, even if you decide to keep the algae eatter (probably a hypostomus plecostomus with the size you described) with temperate water goldfish I would suggest a 75g for the amount of fish you describe. The larger tank would provide a greater chance of the fish living to their full life expectancy, which for goldfish is 20-30 years under good conditions. I understand money being an issue with a lot of people though, so you can always just do what you can and keep making improvements if and when you can afford it.

Thank you for understanding that I am only speaking for all the fishes' ideal situations (ideal situations short of a huge bodies of water, that is), and not meaning to be critical of you personally or your methods of keeping fish.

I hope you enjoy our site as much as we all do.

Mysterywriter221

Thanks so much! I was terribly worried about my fish.

I didn't take any of your critisism negatively. I found it most informative.

Thank you.

Barbrella

What are the ammonia and nitrite readings in your tank?

Ammonia in the water can cause black spots on goldfish as it burns them.

Mysterywriter221

I don't know the readings right now.

If the readings are high how do I lower the ammonia levels?

Lucy

Water changes will help bring your ammonia down, daily until it returns to 0.

Barbrella

If you have 4 good sized fish, including a 10 inch goldfish, in a 30 gallon the odds are that there is ammonia present.

The only solution is to have only the one large goldfish in there, or get a much larger tank. All those goldfish will produce more waste faster than you can eliminate it.

Mysterywriter221

Thanks for the advice. I found the ammonia levels to be slightly high so I have begun following your advice.

Barbrella, I only have 2 good sized goldfish. The others are rather tiny. The 10 inch fish is my algae eater, Dickens.

The ammonia levels have increased only recently. I think it may be because I had to pull the filtering agents out of my filter during the ick treatment.

I hope to resolve the problem soon. Thanks for the advice.

Mysterywriter221

Chief, you were right about Dickens. I looked it up on the website and he is the species you named. Thanks!

Mysterywriter221

I did a 25% water change and my ammonia levels have risen. Should I use OTC ammonia clearing stuff?

Lucy

Odd that the ammonia went up. What're using to test? If you're using the strips, they aren't very accurate.
You should pick up a liquid kit like the API Master kit, very reliable.

Have you tested your tap water?
I wouldn't add any chemical to the tank unless it was an emergency. You can use Prime as your water conditioner, it helps to neutralize the ammonia.
I'd step up the water changes to 50% daily.

Good luck.