Lava is spending a lot of time creating an enormous bubblenest. (see photo) He seems healthy and active otherwise but just doesn't eat as much as he should. I feed him Hikari Bio Gold pellets and he does eat them, but only one and only if it's a small pellet (I have to sort through them to find the smaller ones). Phlox will eat as many as I give him (but he gets only 3 per meal) but Lava will eat only one every few hours. This makes it hard to get enough food into him as I have to work and sleep and can't be there to feed him every few hours round the clock.
Is his preoccupation with building the nest the reason for his weird eating habits? Do Bettas only get obsessed with nest building at certain times (like the way dogs and cats go into heat several times a year) or are they pretty much always ready to spawn? He seems to think he already has eggs in there and is always watching the bottom of the nest for falling fry or searching the bottom of the tank for them. He will sometimes hold a pellet in his mouth for a long time as if it were an egg and sometimes spits them into the nest. Is my fishie obsessed with fatherhood?

Just wondering if this is normal behaviour.
Also, does anyone know if there is a brand of Betta pellet that is smaller in size than Hikari Bio Gold? Maybe a smaller or softer pellet is easier for him to chew.