I would not try a big change just yet. Since you say the eye is cloudy and not swelled I do not think it is popeye. The cloudy look could be any number of things. I say leave it a day or two and see what happens. I do not mean to upset you but I hope you know your betta is reaching near the end of most betta's longevity? Two years or so seems to be about average. Take into account the age the fish was when you bought it and you can see that you have done very well with him. Lets hear how things go in the next day or so. Later.