Can't comment on the Ceylon puffer, but the virtually identical green puffer, Tetraodon nigroviridis, has (apparently) been bred in aquaria. Baensch reports that sexual differences are unknown, they are substrate spawners, and the male fish guard the fry (vol. 1, as T. fluviatilis, though the photograph is clearly T. nigroviridis). I'd venture to suggest that males may be the more aggressive of the two sexes, given that some fish are comparatively peaceful while others more overtly territorial. Realistically, the way to breed these fishes would involve:
-- Raising six juveniles together (to ensure at least one pair, as with angelfish)
-- Removing excess fish once a pair has been formed
-- Likely reducing the salinity to trigger spawning (since the juveniles are freshwater fish)
Cheers,
Neale
PS. The various Tetraodon spp. puffers seem to broadly similar in breeding habits, and several are quite commonly bred. All are substrate spawners, some in caves, some on rocks. Invariably the male guards the eggs, and in some cases the fry, though never for long. Here's an example:
http
/www.dmuratov.com/publications/breeding_nile_puffers/
