An interesting note, when I had my pair of monos in a 150 gallon with the azul and a big Brokopondo and a silver arawana, they would spawn every month like clock work. Since I have put them in the big tank they show the same courtship behaviors they would do right before spawning but they haven't spawned yet and it's been over a year in the tank. My theory is that there is too much activity going on in there now. What do you guys think?