As long as you have sufficient filtration i see no reason why your plan couldnt work.
I have a question about the "bottom feeder" comment. Otos will eat algae, and while that may be something they find on the substrate, they arent bottom feeders as such. They will spend their time grazing wherever algae can be found, on rocks, decorations, off the glass, any plants etc. Are you wanting the otos to carry out a specific role of cleaning up the substrate?