Might I ask why? I'm just curious.
Kissers won't typicaly get to a foot long but can reach around 10" relatively easily. Balloon kissers stay smaller - around 6-8".
Snakeskin gouramies (
trichogaster pectoralis) are another relatively common species that gets quite large - about the same size as an average kisser - but they get there quicker.
Other than those, there are
ctenopoma and
anabas species that grow large and, of course, the various osphronemus gourami species (there's more than one -
o. laticalvus,
o. goramy and
o. septemfasciatus).
Belontia hasselti can also reach about 8" and the pikehead,
luciocephalus pulcher, typicaly gets to just over 7".
Were you after something of a particular size/temperament? If you are, tell us what your criteria are - I'm sure there's a gourami that can get pretty close.
edit: Should add that not all the above are 'gouramies' per say - but they are all quite closely related.
