Hey RAY - The Atabapo II pair (only about 8") spawned in a 55G. holding tank with 11 other similar pikes. Part of a newly imported group, they took over one end of the tank that had a flower pot (on it's side in a saucer). After littlt more than 3 weeks the eggs were laid on the inside top surface of the pot, emulating pike eggs stuck to the top of spawning caves in the wild.
A possible trigger could be the 'group' scenario. Dr. Leibel's marmorata pair spawned in a 75G. tank @ 8" size, maybe young adulthood is a factor. We hope you get 'it' one day Ray, it's just a matter of time until more Pike spawns are happening.
Seiichi ~ any info on your friends' tank set-up, conditions, etc. for their Atabapo spawns???