HELP! 20 gallon has fungus!

[Maryrox247]

My filtered and heated 20 gallon has a fungus issue! The tank is cycled and the temp is usually 80 degrees. The substrate is gravel and there are no live plants. I do about a 50% water change every 2 weeks and clean the filter pads (or change them it depends) on the same schedule. It is divided in half for one male and one female betta. The female is constantly having stress stripes but otherwise acts energetic and normal. The male acts normal too, eats fine and all but today i noticed he has a white patch on his side and a little white moustache. (fungus!) I have jungle fungus clear and i know to use 2 of the fizzy tablets for the tank but i dont know what to do aout the filters or the water change and new medicine dose schedule (It does not say on the instructions) Please help as fast you can! (Thank you!!!!!!!)

[Luimeril]

if i'm not mistaking, you take out the filter media during. then, do partial water changes every day. it's been a while since i used any meds, and my tanks aren't cycled. x-X