Had this same problem before, it turned out i didnt have a proper on off scedule for my lights and there was algae everywhere. I cut down to 6 hrs a day for a week and bought another pleco. Bam no more algae
$30-$40 for a UV light is not that bad, and if you ever need it in the future, it'll always be there for you. My 3 tanks, each took turn blooming algae, and the UV helped tremendously. Good luck!!