I've (had) have 2 golden sleepers. Both readily eat anything not nailed down. Even seaweed as the tangs rip it up. After feeding i can see a noticeable bulge in its belly so its definitely getting it in.
I was at a lfs last week. The one owner was talking to a customer and sw came up. The owner told him 90% of the people that get into sw only last a yr. I was shocked, but it seems consistent unfortunately