Hey fish folks....


12 Years
Feb 15, 2007
Austin area, Texas
I've had goldfish in my pond for a couple of weeks. One of the apricot blush comets is developing black spots on its side. Is this a disease or a natural color variation. I've moved the fish to one of the pools on the stream so it is a little away from the other fish. I don't currently have a water testing kit, but I will be picking one up tomorrow. The pond is fairly new, has a 12 foot long stream and waterfall, a 4 x 8 foot bog garden planted with irises, papyrus, cat tail and some trailing red water weed. The water is crystal clear but I am getting a little algae growth on the rocks of the stream.

Thanks for the help.
Any chance we could see some photos? How do the gills, fins, and mouth look? Anything look tattered? Any gasping or hanging at the bottom or near the surface of the water?
The fins, mouth and gills are all looking good. The fish is fast, healthy and eating. It took me 15 minutes and another person to catch the bugger to look more closely. These guys are fed 3 times a day, and eat everything in about 2-5 minutes. Up close, it didn't looked like scars or scabs, but merely scales that had changed color. One other of the apricot comets has one or two spots, the other comets, fantails and shubunkin all appear normal. Yesterday there were no black scales at all. The affected fish has swum downstream and rejoined its friends.
So glad he is showing signs of being healthy. It's a bugger to have one take the others down too! The water testing kit is a good idea. Many places will test your water samples for free too. For black scales, look for off kilter PH or high ammonia levels in particular.

Since it doesn't sound like he has any growths or gick, and that it is actually the scales turning black, here are some common causes for that:

- http://www.kokosgoldfish.com/Melanophore%20Migration.html
- http://www.petgoldfish.net/black-spots.html
- http://www.fishlore.com/fishforum/freshwater-fish-disease/94012-new-comet-turning-black-other-fish-not.html

lighting that was mentioned can also include sunburn (usually this happens in a fish that stays too close to the surface, which may indicate another health issue). So, you are probably looking at some sort of tissue damage, regardless of the cause. Keep a close eye on it, and their behavior, and see what the water results say. Hope all ends up well.
I fed them this morning, and all appeared normal except for the one with the black spots. Again the fish appears healthy, is eating and active with no scraping its body along the bottom or plants or anything else.

I'm off to the pet store soon for a test kit and cat food.

One of the posts said low pH could be a problem. But high pH is more likely in my pond since the tap water tends to the basic and the pond is lined with limestone. I'm off to look at goldfish pH requirements...
Most shoot for neutral, and many allow wiggle room of about six to eight. I think I heard that high ph or low ph can both cause tissue damage, and thus black scales. If I ever get my aquaponics system up and running, I know you have to be careful when adding any sort of nutrients for the plants, because a lot of people end up burning their fish that way! But, a lot of aquaponic sites (try the diyaquaponic forums) have good advice on how to raise and lower pH effectively and at the right pace, since they have to be really careful to keep things balanced.
If your pond is lined with limestone, it is highly unlikely you will be able to keep your pH anythiing different than it is right now. Although 7 to 8 is ideal, fish can lean to adapt to pH as low as 5.5 and as high as 9 with no issues. The main thing is keeping the pH stable though proper levels of alkalinity. And the limestone in there will add sufficient kH (alkalinity) to keep the pH stable. Any addition of chemicals in an attempt to lower the pH will probably be unsucessful and the shifting pH is a big problem for fish. Stable and high or stable and low is MUCH better than unstable and moving around. As long as the fish are healthy and act fine, leave the pH alone. The only possible bad thing about a high pH is that ammonia is much more toxic in a higher pH situation. Ammonia levels that are not harmful at a pH of 5.5 could be deadly at a pH of 8.5.

In an aquaponics set-up, pH is much more critical because of the plants.
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Goldfish are pretty hardy, one reason they are popular pond fish, but closer to neutral is more ideal for them. They can definitely survive a wider range (and a wider temp range than many), but it sounds like the OP is interested in good scale quality, etc. So, even though they are definitely more picky about pH than the average pond goer, I still suggest aquaponics forums.
. Many have good tips for adjusting the pH very, very slowly, and then keeping it stable. And horror stories about what happens when you change it too fast...excellent point that low or high stable are much better than jumps. Even on rock surfaces that change the acidity, they have a lot of good tips for liners, sealants, and water additions that can help, and can help in keeping very long lived fish in good condition.
. Lots of creative people out there with lots and lots of good advice.
I tested the water...no traces of nitrate or nitrite. The water is hard, no big surprise there, and the pH is running about 7-7.5, so close to neutral but on the basic side of things. So it probably isn't a pH or ammonia issue, and I treat all the water I add to remove chlorine and chloramine.

I'll keep watching the fish.

If you can point me to a good aquaponics forum or two, I'd appreciate it.

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