White And Black Patches On Goldfish


New Member
Hey all.

My brother got a goldfish recently and we started to notice these weird patches on it. Not sure about the black spots but is the white ich? I was just not sure because it is only in the one spot on his head and no where else. Not sure if the different marks are related or not. Sorry for the not-so-great pictures but its hard to get a good picture of a fish that's always swimming, any help or ideas would be greatly appreciated



Fishlore VIP
The black blotches on your gold fish are called "Black Smudge". Its a symptom of bad water parameters, probably an ammonia spike. Best to change out 50% of the water and use Prime water conditioner. It temporarily nuetralizes
ammonia. Change 50% of the water each week, and don't overfeed. Hope he gets better soon.


I see in your aquarium info that you are unaware of the nitrogen cycle (words should be link to article explaining it). I highly recommend your read up on it and fully understand it. It is the very most important thing to understand when keeping fish. Once you are aware of the nitrogen cycle you will need to come up with a strategy for cycling the tank. Since you have the fish in the tank already you will need to do what is called a fish-in cycle (as opposed to a fishless cycle). There are basically two ways to do this. One is the hard way, the other is the easy way.

The Hard Way:
1) Buy a bottle of SeaChem Prime. Prime is a water conditioner that can detox upto 1ppm of ammonia and/or nitrites for 24 hours.
2) I recommend the API Master Test Kit for Freshwater. Stay away from the test strips. They are notorious for being inaccurate, and if you can't trust the results, why bother testing.
3) Test your water daily. If ammonia+nitrites is 1ppm or less add enough Prime to treat entire tank volume. If ammonia+nitrite is greater than 1ppm, do a large enough water change to get it under 1ppm. Add enough Prime to the new water to treat entire tank volume. (Note your ammonia and/or nitrites may be so high initially that you may have to do some back to back water changes to get the ammonia and/or nitrite levels under 1ppm).
4) Repeat this process daily until your ammonia level is 0ppm, your nitrite level is 0ppm and you have some nitrates. At that point you are cycled and will only need to do weekly water changes to keep your nitrate level under 20ppm
5) Note this can tank up to 6 weeks to finish cycling. You could use a product be SeaChem called Stability which may help speed the process up a little.

The Easy Way:
1) Get a good test kit. (see number 2 above)
2) Get a bottle of Tetra SafeStart+ that is large enough to treat a tank at least as large as your tank (don't worry, you can't overdose with TSS+)
3) Do a large water change, or even back to back water changes to get your ammonia and or nitrite level as close to 0ppm as possible.
4) Wait 24 hours minimum. (THis is extremely important since using any water conditioner less than 24 hours before adding TSS+ can cause it to fail
5) Add entire, well shaken bottle of TSS+ to tank
6) Do nothing but lightly feed your fish for the next 14 days. (No water changes, no adding chemicals...nothing
7)On day 14 test, and if all worked correctly...you're cycled.

But here's the real problem you may be facing. These methods assume you have healthy fish. But if you need to medicate the tank, you may not be able to do what needs to be done to cycle. Some meds don't allow water changes for several day, so the first The Hard Way is out, and some meds may interfere with the TSS+ and if they don't, need you to perform a water change after 4 or 5 days, which could cause the TSS+ to fail, so the Easy Way could be out.

But I have little doubt that your fish's illness is caused by the effects of being in an uncycled tank. I've never heard of "black smudge" before, but I can believe the claI'm it is caused by elevated ammonia levels. The white stuff look like a fungus to me (hard to tell from the photos) which can also be brought on from being in an uncycled tank. If it were ich, it would look like the fish was sprinkled with ich.

To be honest with you, you would be in less of a bind of it was ich, since that can be cured thru elevated tank temps and water changes. But for a fungus, you will need to treat with a med, such as Tetra LifeGuard. You want a real antibiotic, not one of those herbal remedy's such as MelaFix.

So like I said, your in a bit of a bind, but if were me, here is what I would do. I would cycle my tank with the TSS+ as outlined above, and I would add the meds and hope for the best. I think I might add the TSS+ then try to wait 2 or 3 days before adding the med. Then just wait until day 14 to do the water change, even if the directions on the med tell you to do it sooner. One very important thing: Remove the carbon from your filter before doing anything if you are going to use my recommended method. Depeneding on your filter, you may have to cut a slit in the floss and dump the carbon out. Just make sure you leave the floss if that is the type of filter you have. The reason is that carbon removes meds, so if you leave it in, it will strip the meds from the water. And the reason to do it before adding the TSS+ is that the bacteria that cycles your tank lives in the floss (if that is the type fo filter you have) and you don't want to disturb the newly settling in bacteria (TSS+ is basically a bottle of the bacteria that would develop naturally over the course of 6 or so weeks).

Okay, this was pretty long and took a lot of time, so my expectation is that you will successfully get your tank cycle and save your fish (no presuure right?) ! I'm teasing you a little with that, but seriously I want to wish you the very best of luck. I will admit that I have a soft spot for goldfish. For some reason they are really easy to become attached to. So I truly hope all goes well.

And lastly, I'd be surprised if you didn't have any questions, so feel free top ask any questions you may have, We have a lot of helpful, knowledgeable who will be more than happy to answer any questions you may have. And no one will ever think any question you ask is stupid and demean you in anyway for asking.

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