Canadian goldfish with mouth issue: help!

[Lisa.d.ranged]

Bruce is about 8 years old and lives in Canada, where we are no longer able to buy most aquarium medications. Bruce injured her mouth presumably by swimming into a piece of spider wood on August 16th. She had a bruise on the inside of mouth, a tear in her bottom lip, and a few scrapes on the top lip, all on the right side. (See photo above.) Initially we treated her with Maracyn, but her 75 gallon tank used our entire supply for just one dose. We also tried API Super Ick Cure at the same time in case there was a fungal component.  The split lip and bruises healed very quickly, but the abrasions have been getting better and then worse again, over and over. This her today.She is eating, pooping, and acting normally, but her poor mouth just won't heal. We don't know if this is a secondary infection of bacterial or fungal nature, or something else entirely, but either way it is difficult to get any medication here. If we could get an accurate diagnosis, we can focus our efforts on obtaining the right treatment. Can anyone shed some light on this for us?

[Colu]

Were the injury is on the mouth it will take longer to heal  what I would do is add some aquarium salt 1 table for 2 gallons for a week that will help to provent secondary bacteria infection will aid Gill function and add essential electrolytes just remember to only add back in the amount of salt you tank out so if you do a ten gallon water change add 5 table spoons of salt back in 

[Lisa.d.ranged]

On 9/18/2022 at 4:48 PM, Colu said:

Were the injury is on the mouth it will take longer to heal  what I would do is add some aquarium salt 1 table for 2 gallons for a week that will help to provent secondary bacteria infection will aid Gill function and add essential electrolytes just remember to only add back in the amount of salt you tank out so if you do a ten gallon water change add 5 table spoons of salt back in 

I forgot to mention that we have been using 1 tbsp. of salt for every 3 litres of clean water we are putting in, and that has been since the initial injury. 

The original wounds are healed, but she keeps getting this problem where this tissue on her mouth looks like it is sloughing off, then it improves and almost looks normal, then it starts sloughing off again.

[Colu]

What I would do is stop using the salt as it doesn't seem to be helping I would start adding some API stress coat and increase water changes to keep the water pristine that should help speed up the healing process as it sounds like it could be over production of the slime coat around his mouth caused by the injury @Lisa.d.ranged

[jwcarlson]

Is there anything sharp in the tank?  I know some goldfish will kind of aggressively "clean" gravel, is it possible he's re-injuring his mouth doing that?  The rock at the base of driftwood or *something* in that first picture looks pretty sharp?