Do otos really only eat algae?

I think you are confusing the Otos with the Chinese algae eaters, or the Indian algae eaters, those might go after the slime coat of other fish. From what I see Otos are safe and do a great job.
 
My otos eat algae wafers and regular flakes, as well as algae off the glass/plants/rocks. Sometimes they get so excited when I drop a wafer in, they go into a frenzy and suck onto everything, including the other fish. I don't think they're trying to get the slime coat, it really just seems like they're overexcited about the wafer and don't know what to do. It's the only time they touch the other fish.

I have a video up that shows the wafer frenzy: http://www.youtube.com/watch?v=d-jUVPrMhMA.
 
Ha! I didn't even notice that!
 
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