Sick Firemouth Cichlid

[Mw1234]

Hi, wondering if anyone can advise what this infection might be (bacterial /fungal).
My firemouth has been looking like he is gasping for a few weeks now and just mostly lethargic and not eating. At first he was sitting at the bottom of the tank then after some water changes he was hanging near the surface next to the heater but now is back to sitting at the bottom of the tank.
I have been doing regular water changes and increasing aeration but he is not improving. 3 days ago I noticed these white spots near his gills and I have been treating with Melafix although about half the recommended dose as I am worried about bad reports using this. I have ordered some aquarium salt and tri- Sulfa tablets online (local pet shops closed during lockdown) but they will take up to a week to arrive.
Pics below, Ignore the clouded eye as he has had that for a few years and it hasn’t seemed to impact him.

Water levels seem ok. Ammonia and nitrite 0, nitrates 5

Also I’m not sure but he sort of looks bloated on this side near the top fins compared to the other side.

 

[Autumnsky]

Do you know your pH and
KH/GH,
TDS

What is the size of the tank, other tank mates, any new additions of plants or inhabitants in the past few months?

What is the maintenance schedule you have for the tank?

Here is some info and check the external parasites. Fish Lice, body and gill flukes, Ich
https://www.aquariumadvice.com/fish-disease-index-for-diagnosis-and-treatment/

 

[Mw1234]

He is the only fish in a 60ltr tank.
When I noticed him not well I did a water change 25% that day and increased aeration. unfortunately I forgot to test water prior to the first change however 30 mins after I tested and the the nitrates were high, around 20 and ammonia was somewhere between 0 and 0.25 (hard to tell with testing kit) so I did another 25% change. 2 days after that I a small water change to clean the filter which hadn’t been cleaned in a while.

I have did a few more 25% water changes since then and the water levels are now seem ok I think:
Ammonia I think is 0, again hard to tell with the testing kit but it definitely looks more yellow than green.
Nitrite 0
Nitrate 5
ph 6.8
Temp 26degrees Celsius

 

[Mw1234]

Also I have tried looking on so many websites but it’s hard to match this white spot with anything which is why I am unsure. I thought cotton wool disease but then it doesn’t exactly look like other images I have seen online.
This is the only spot on his body
More concerning is the gasping for air, it is just constant regardless of aeration.

Do you think it would be beneficial doing a salt bath or something? I only have Rock salt. All the local pet shops are closed and delivery is taking forever.
I don’t want to stress him out more

 

[Autumnsky]

A 60Ltr tank would be around 15G. 115ltr would be a better size for him. So maybe there is some stress with a smaller space.

Your filtration might be under what it needs to be.

And of course if you got a larger tank, it would need a filter rated to the tank size.

Is your filter media cycled with a long term colony of beneficial bacteria? This would be seeded with previous established filter media or established long term, and rinsed only with treated/ dechlorinated water so as to preserve the BB colony. If you changed the filter pads/media or washed them in plain non treated tap water.

I would look into the gills for any tiny creatures. But if you had an ammonia spike after changing a filter pad he could have got ammonia poisoning and had some damage to his gills.

Did you check the article link?
https://www.aquariumadvice.com/fish-disease-index-for-diagnosis-and-treatment/

This might have something you can check for.

 

[Mw1234]

Thank you for the response. Yeah I also thought about space so I have removed/ moved ornaments to give him more room.
I have had him for about 8 years so the tank is well established. I haven’t changed the filter sponge recently but I usually only squeeze it out in aquarium water when I’m doing a water change.
Is ammonia poisoning reversible?
I have just been able to get some broad spectrum remedy so I am going to try that instead of Melafix and I also added a tiny bit of Cichlid salt today.
With the salt I was a bit confused, I have never added salt before so should I dose as if it was a new tank? (It says only dose according to the water being added). It says 1/4 tsp for 110ltr tank so I only added the tiniest amount