So I don't have alot to go on.... I was at a Big Al's in Whitby, and they have a lovely shimp display tank, heavily planted with 15 or so different varieties of shrimp, and small algae eaters... They could not ID them nor did they have them for sale. Apparently the display tank predates any of the current employees. They were a small lithe algae eater, seemed to do its job well, with a "sucker" larger then their head a bit. They had an unusual fin configuration, rounder fins with a 2 sets down the length of them. They were an 1 to 1.5 inch tops. They were kind the standard "algae eater" brown, but they had some blue in their finds just a bit, but that may have been the light. Not regular otos for sure. Not sure what they were. They looked Shrimp safe. The round fins and very narrow body (even compared to other algae eaters) were prolly the most distinct feature.