My female Koi/Marble betta fish seems to have a cloudy(?) eye. She also spends most of her day glass surfing on the front and back of the tank. She glass surfs more than any betta I have ever owned to the point of concern. Parameters: Ammonia: 0 ppm Nitrite: 0 ppm Nitrate: 5.0 ppm PH: 7.6 ~ The tank she is in is a Fluval Spec V, (so 5 gallons) This tank was set up 12 days ago with adding TSS exactly per directions, (on day 9 of TSS I started making PWC using Prime about 30% every 2 days because of the concern of cloudy mucous eye.) I also monitored this tanks water conditions like a hawk every day because I was doubtful of TSS, but it seems to be working well for me at least. I have just made a water change again 2 days later after my first water change of around 35% dosing with prime. I have not added any medications because I cannot identify the reasoning of her obsessive glass swimming and cloudy eye. She has relatively soft plants. not silk but not the cheap kinds, a sand substrate and a few aquarium pebbles. I also buffered the flow of the Fluval Spec V with the Fluval prefilter sponge. To help her glass surfing I've lined the plants to the back of her glass swimming path, turned off the lights, added a white paper backing to stop the reflection, it seems to not be changing anything. I am not sure what kind of filter the Fluval Spec V is, but I use both carbon activated, sponge inside and the bio pellets. It is only her in the tank. I have put an Indian almond leaf into the tank, she also has a stable temperature of around 78 degrees monitoring the thermometer and heater. I had gotten her from petco approximately 12 days ago, and acclimated her in her cup for awhile before putting her in. I feed her and my male freeze dried blood worms and 1-2 pre-soaked pellets. Any advice/help would be much appreciated as I'm concerned for her. Hopefully the picture I attached shows you the strange mucus cloud on her right eye well enough. She doesn't stay still much and tries to eat everything. Thanks!