Dwarf gourami help!

[Clare4695]

So ive had my dwarf gourami in a 120l tank with some shrimp, five lemon tetra, 8galaxy rasboras, 8 pygmy cories and 4 guppys for about 8 months and it was doing great. About 3 months ago i noticed he was kinda chubby but scales were fine and he was eating perfect and all was good. About a month ago i started noticing that he was getting fatter on one side and then this growth started to appear on his eye but comes and goes. About 2 weeks ago the scales started to lift on the fatter side and about a week ago i saw the scales in the otherside where abit too and he was starting to not eat as much. Tonight i have seen he is just laying on top of the filter. Not sure what could even be going on to be able to treat it or if its wvem treatable. All my levels are good and i clean the tank regularly and my filter is really good and all other fish a shrimp are all perfect!