How big was Leedsichthys?

Perhaps the biggest bony fish in the Mesozoic
Leedsichthys problematicus (Woodward 1889, Martill et al. 1999; Middle Jurassic; holotype BMNH P.6921; Fig. 1) is known from several impressively large specimens including a caudal fin, pectoral fins, a hyomandibular pllus gill basket (Fig. 1). Large gill rakers appear to have been capable of filtering plankton.

According to Wikipedia,
Leedsichthys is a giant member of the Pachycormidae. That seems reasonable, given what is known. These are too few parts published in articulation to add to the LRT.

Skeletons were largely cartilaginous,
rather than bone. Length estimates have varied considerably from nine meters to thirty meters (100 feet). Recent research considers 16m a plausible estimate. Here, using Bonnerichthys as a template, that matches precisely those ‘plausible’ estimates. The big caudal fins is from specimen NHM P.10000 (from Liston et al.. 2013).

References
Liston J, Newbrey M, Challands T and Adams C 2013, Growth, age and size of the Jurassic pachycormid Leedsichthys problematicus (Osteichthyes: Actinopterygii) in: Arratia, G., Schultze, H. and Wilson, M. (eds.) Mesozoic Fishes 5 – Global Diversity and Evolution. Verlag Dr. Friedrich Pfeil, München, Germany, pp. 145–175.
Woodward AS 1889. Notes on some new and little-known British Jurassic Fishes. Annals of the Magazine of natural History, series 6, 4: 405-407.

wiki/Leedsichthys