I started hand feeding Optimal to my BG about two months ago. While I see some eating it, I do see a lot of them spitting it back out. I'm only there on weekends so they only get it a few times a week. The majority of it gets eaten by CC and turtles. I've got native BG that are not pellet trained and some Ots CNBG which I assume are the ones that don't spit it out. Guess I'll just keep throwing it out there see if they take to it.
What I have observed with any feed is if the pellet the fish takes is hard and it is a little on the big size for them they will spit it out (often with a larger fish right behind them that takes it in and keeps it). If it has been in the water long enough to be softened they will retain it.
If you are feeding pellets that are fairly big in relation to the fish size I think you will see more of this spitting the feed back out till it softens. I feed a little bit of AM400 (which is a BB size pellet) in the shallow water for my 2-3" BG. I often throw just a few of the larger AM500-600 mix just beyond to keep the larger fish interested away from the high protein AM400 (all the fish love the 46% protein AM400, even 3# CC). I see a 3" BG hit an AM500 pellet and spit is back out (because of its size and it is still hard) but they never spit out the AM400 which is smaller.
I believe size of pellet in relation to the fish size and if the pellet is dry or hydrated has a lot to do with the fish spitting a pellet back out.
