Not sure, it looks 12", but the tail is bent, probably around 13-14"!!!
The info card covering the polypteriformes, has the ropefish listed as 'calamoichtyes' which is an old taxym for that fish. I'm guessing this was setup in the early to mid 90's, bichirs weren't as popular back then as they are now, so I'm guessing it was a wild caught one near full size.