THe growers pellets I use are slightly smaller than layers, do you know anyone nearby who would let you have a small handfull (if the same make of course) to compare? and one was slightly paler than the other.
Giving them 50/50 till you fnd out or buy some more growers seems the safest way.
I loved my buffs, they do look funny when they come 'running' towards you. But they always looked so bedraggled when they'd been out in the rain (their choice

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