Grey spot on tail fin

[Caretta Rose 93]

This morning I noticed a grey spot on the tail of one of my goldies. I don't remember this being there before. It almost looks like a pimple of some sort. Could it be a fluke? I've attached a video below. There is also a patch of grey at the very end of the tail fin that was not there before and I'm not sure if this is a normal colour change?

Behaviour is normal and looks otherwise healthy. Any thoughts as to what this might be?

EDIT:

Here are some stills, the video quality isn't the best.

 

Edited November 25, 2018 by Caretta Rose

[koko 14,340]

Please copy & paste fill the following form and fill it out to the best of your ability when requesting help for Goldfish Problems: 

Test Results for the Following: * Ammonia Level(Tank) * Nitrite Level(Tank) * Nitrate level(Tank) * Ammonia Level(Tap) * Nitrite Level(Tap) * Nitrate level(Tap) * Ph Level, Tank (If possible, KH, GH and chloramines)  * Ph Level, Tap (If possible, KH, GH and chloramines) Other Required Info: * Brand of test-kit used and whether strips or drops? * Water temperature? * Tank size (how many gals.) and how long has it been running? * What is the name and "size of the filter"(s)? * How often do you change the water and how much?

* How many days ago was the last water change and how much did you change? * How many fish in the tank and their size? * What kind of water additives or conditioners? * What do you feed your fish and how often? * Any new fish added to the tank? * Any medications added to the tank? * List entire medication/treatment history for fish and tank.Please include salt, Prazi, PP, etc and the approximate time and duration of treatment. * Any unusual findings on the fish such as "grains of salt," bloody streaks, frayed fins or fungus? * Any unusual behavior like staying at the bottom, not eating, etc.?

[Caretta Rose 93]

Test Results for the Following: * Ammonia Level(Tank) 0 ppm * Nitrite Level(Tank) 0 ppm * Nitrate level(Tank) 10-20 ppm * Ammonia Level(Tap) 0 ppm * Nitrite Level(Tap) 0 ppm * Nitrate level(Tap) 0 ppm * Ph Level, Tank (If possible, KH, GH and chloramines) 8.2, KH 120 ppm, GH 120 ppm * Ph Level, Tap (If possible, KH, GH and chloramines) 8.0, KH 120 ppm, GH 120 ppm Other Required Info: * Brand of test-kit used and whether strips or drops? API Freshwater Master Test Kit, dip strips for KH and GH * Water temperature? Approx. 18 Celsius (64.4F) * Tank size (how many gals.) and how long has it been running? 75 US Gallons, running since Aug 4 2018 * What is the name and "size of the filter"(s)? Fluval FX6 * How often do you change the water and how much? 90% once per week

* How many days ago was the last water change and how much did you change? Yesterday (Nov 24 2018), 90% * How many fish in the tank and their size? 2 goldfish: 83g and 93g (fish in question is the latter) * What kind of water additives or conditioners? Seachem Prime each wc * What do you feed your fish and how often? Various foods, once per day. Fast one day per week. 1) Hikari lionhead mini-pellet (staple), Omega One sinking goldfish pellets (occasional), assortment of fresh leafy greens (mainly kale or spinach) once per week, frozen bloodworms (once per week) * Any new fish added to the tank? No * Any medications added to the tank? No * List entire medication/treatment history for fish and tank.Please include salt, Prazi, PP, etc and the approximate time and duration of treatment. A Prazi treatment on started on Sept 11 with 70% wc and last dose Sept 27 with 70-75% wc. Have not used salt or anything else. * Any unusual findings on the fish such as "grains of salt," bloody streaks, frayed fins or fungus? One fish showing a grey growth or "attachment" to tail fin - noticed this morning. Also noticed a dark colouration at end of tail. See photos/video in first post. * Any unusual behavior like staying at the bottom, not eating, etc.? Behaviour appears normal, both fish interacting, active and foraging, no loss of appetite.

Edited November 25, 2018 by Caretta Rose

[koko 14,340]

It also looks like there is a torn fin too.

 

I would do for now is a salt treatment on the tank. Since you already did a Prazi round in September. If we have to we can do another round of praziquantel.

I would go with .3% (once you get it up there) for a week and let me know how they are doing.

What kind of plants are in the tank. Some plants don't mind the salt others will melt.  

[Caretta Rose 93]

OK. I should have some time tomorrow to start the salt treatment. The plants in the tank are Anubias on the driftwood and I also have a moss ball and some pothos rooting in a basket.

[Arctic Mama 3,625]

Man we are having trouble with the disease diagnostic form.  Koko, can we reformat that original post from T D in plain text or something so that it comes across better when it’s in thread here?

[Arctic Mama 3,625]

And Caretta, am I understanding this is a fairly new tank?  Running since August?  It is technically possible the grey thing could be a fluke, though you’d expect to see those show up on fish sooner than a few months, they can hitchhike on other livestock and plants.  

 

Can you summarize for me when you added each fish and plant?  If all of it went in at the same time, that would probably eliminate some ectoparasites from consideration of treatment just by timeline, unlsss you’re feeding live food.

[Arctic Mama 3,625]

35 minutes ago, koko said:

It also looks like there is a torn fin too.

 

I would do for now is a salt treatment on the tank. Since you already did a Prazi round in September. If we have to we can do another round of praziquantel.

I would go with .3% (once you get it up there) for a week and let me know how they are doing.

What kind of plants are in the tank. Some plants don't mind the salt others will melt.  

Yes the salt might not play nicely with plants, but neither would a number of other treatments for bacterial infections or parasites, so it’s a good starting point.

[Caretta Rose 93]

52 minutes ago, Arctic Mama said:

And Caretta, am I understanding this is a fairly new tank?  Running since August?  It is technically possible the grey thing could be a fluke, though you’d expect to see those show up on fish sooner than a few months, they can hitchhike on other livestock and plants.  

 

Can you summarize for me when you added each fish and plant?  If all of it went in at the same time, that would probably eliminate some ectoparasites from consideration of treatment just by timeline, unlsss you’re feeding live food.

Hi Taryl,

 

Yes, this is a new tank running since this summer. It was fully cycled on August 23rd. Plants were added before the fish, sometime in early August. Unfortunately I don't have exact dates for the plants. All aquatic plants that I added before and after fish were soaked in a bleach solution before adding them to the tank to kill off any potential buggers. The most recent plants were added about 4 weeks ago. 

Both fish were purchased from the same store, same tank, and put into my aquarium on September 8th. I initially started a Prazi treatment because I noticed both of them 'yawning' quite a bit. I am still noticing them both do this, but a lot less than at first so I wrote this off as normal behaviour. Maybe I am wrong! 

Both fish are fairly hand-friendly, should I attempt to poke at this thing a little bit and see if it's external? Or would this cause unnecessary stress do you think?

Edited November 25, 2018 by Caretta Rose

[koko 14,340]

I wouldn't poke it, but if you can feel it. 

Does it feel hard or squishy ? 

[koko 14,340]

On 11/25/2018 at 10:53 AM, Arctic Mama said:

Man we are having trouble with the disease diagnostic form.  Koko, can we reformat that original post from T D in plain text or something so that it comes across better when it’s in thread here?

I started a report about this  

[Caretta Rose 93]

2 hours ago, koko said:

I wouldn't poke it, but if you can feel it. 

Does it feel hard or squishy ? 

It feels somewhat squishy. I looked a bit closer today and it almost looks as if it could have been a result of some nippage from the other fish... possibly. It looks like bite marks, almost? I'm wondering if the other was nipping and ended up tearing the other's fin, and an abscess appeared while it was trying to heal? I have not started salt treatments yet but I will hopefully have some time tomorrow.

[Arctic Mama 3,625]

It could be, or it could have been internal weakness/rot that essentially melted the tissue in that area.  I had a fish with a spot like that on his tail earlier this year and it was part of an underlying viral something or other.  Just one symptom of his weakened immune system.

[Caretta Rose 93]

Quick question regarding salt. Do I also account for the volume of my canister filter? Or just measure out the appropriate salt for just the 75 gal aquarium?

[koko 14,340]

17 minutes ago, Caretta Rose said:

Quick question regarding salt. Do I also account for the volume of my canister filter? Or just measure out the appropriate salt for just the 75 gal aquarium?

Just the salt for the tank  

[Caretta Rose 93]

OK, thanks Shannon. I just want to make sure I'm doing this correctly - it is 1 level teaspoon per gallon of aquarium water? I have never salted a tank of this size and it just seems like a lot of salt to me!  I've measured out ~70tsp for the 75 gallons. And then I repeat this again 12 hrs tomorrow and then 12 hrs the day after? 

Edited December 3, 2018 by Caretta Rose

[Arctic Mama 3,625]

Are you aiming for .3% solution in the water? If so then yes, the 12 hour dosing is good,  just remember If you do any water changes to replace the salt lost in those gallons of water, and do it at the 1 tablespoon dose since they are acclimated to .3% salinity already.

 

I usually scoop mine into a separate bucket with some tank water, refill the tank and dissolve all my sat and meds, and then use my hand to scoop the fish back into the prepared new water.