You're running short on time this year to feed. Usually feeding dry food stops around low 60 degree water temp.

In a pond setting, with a whole bunch of different sized fishes, from that range of food, I'd go with the 3.5mm floating.

I've seen BG as small as 2" pecking at AM600, which is around 1/4" or slightly larger.

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3/4 to 1 1/4 ac pond LMB, SMB, PS, BG, RES, CC, YP, Bardello BG, (RBT & Blue Tilapia - seasonal).