Cories do much better in groups of 6+, are you very attached to the ottos? Cuz you could get rid of them and get 6 cories instead. Pygmy cories are great if you want to fit a larger shoal. Honestly, your bottom will be very crowded with 6 cories (of any size), and 2 ottos. I'd recommend dropping the ottos, as they can be very delicate species. If you want someone to help clean the algae then get a few cherry shrimp, they're quite cool looking and very good housekeepers!
Oh, and wait! Your tank is not cycled yet, is it? I thought you only set it up this week or last week. Def. don't add ANY more fish until your tank is done cycling. When your tank is done, go ahead and add them, but don't add them all at the same time or your tank will go through a mini cycle again. Ottos are particularly sensitive to water quality, so they won't survive if you add them now.