Please help! Interpet Antibiotic Reaction

[AmysAngel]

I'm beside myself with worry and would love advice if anyone can help. I have a beautiful Angelfish, she is 4-5 yrs old, in a tank by herself and has always been so healthy. I noticed a hole forming in her dorsal fin and it started getting bigger. Terrified, I did the worst thing and did a Google search which told me to treat her with antibiotics straight away. I used Interpet fin rot treatment and followed the instructions perfectly, but noticed she was spending more time at the top of the tank later in the day. I was worried about oxygen levels so did more google searching and saw that a lot of people had reported their tanks being starved of oxygen from this treatment, causing their fish to pass out or die! They recommended water changes straight away and not sure what to do, I contacted Interpet customer services (still with no reply). I did about 15% water change and kept the bubble tube and filter going (with carbon removed, but not sure if I should put that back now). I woke up yesterday morning to find her alive but flat at the bottom of the tank. I started doing water changes based on posts from others that experienced this, but today I was sure she had passed away as she had stopped moving entirely. I sobbed my heart out and prepped myself to give her a little burial but then she moved her eye and waved her little fin. I was so relieved, so did another water change, about 30% this time. Her gills are flapping again, so I have a bit of hope, as other had said they thought theirs were dead, but it had just been knocked out sleeping for a couple of days then came back.

Has anyone been through this or have any advice? Shall I keep water changing? Should I put the carbon back in the filter? Should I adjust the temperature? Should I feed her while she is down? Is there a chance I can help her?

 

[Naughts]

I would do a 75% water change (dechlorinated and temperature matched) and add back the carbon. I wouldn't adjust the temperature unless it is out of range (76-86/ 24-30) nor feed at the moment.
The meds won't be antibiotics as that needs a prescription, but will be anti-bacterial and anti-fungal.

 

[AmysAngel]

Thank you so much xx