I agree with Colin. A video will be more useful.Can you try taking a short 20 second video of the fish? The footage might be clearer.
Post the footage on YouTube and copy & paste the link here.
Hold your phone horizontal so the video fills the entire screen.
You really should clean your tank once a week. Vacuum the substrate and do a 70% water change each time. Clean your filter media in tank water every 2 weeks.Tank is 30 gallons test strip says GH 60, KH 40, PH between 6.0 and 6.5, NO2 0, NO3 40. I do a water change every two weeks and it's due tomorrow which is why that last number is higher.