I have a lone sae, and yes he is definately a true sae, in my 250L planted tank, he's fully grown at around 6" long and very placid. There isn't a lot of algae in there now for him to eat but he still constantly searches for food. He eats just about anything, flake, catfish pellets, bloodworm, tubifex worm, brine shrimp, dafnia, cucumber, spiralina pellets, algae wafers and snails. Yes snails, man I love this fish for that. He/she picks them off the glass in front of me regularly showing a marked peferance for the tiny baby ones. In fact this fish seems to be constantly eating given the chance.
About the only downside is that I would never be able to catch him (without taking all my plants out) as his turn of speed and mastery of his enviroment is simply awesome. Sometimes when startled he bolts (super fast like) which can cause my other fish to be a bit skittish but its a small price to pay for a valued member of my clean up crew.
Regards, Chris.