My Amanos are the ultimate escape artisits. Until I realise this I lost a few - and my tank is covered. I have since taped up ALL holes / escape routes. This was in the days when my tank was cycling - they are very VERY sensitive and probably tried to escape because of this. I know this is not great news - look on the floor! BTW, they can crawl VERY far, some of my unfortunate escapees made it up to 6 METERS before conking out. - They are like moths in this respect - they head for light....
To entice them out - I find that when I do a water change they go swim all over the place.
Hope the lost on is OK,
Andy