I do the same but use wheat bran instead of oats and potatoes rather than carrots .(POTATOES ABOUT ONCE A MONTH ) . I now have 4 trays .
Eagle 1 You say you have 4 bins..Are they the stacked kind with 1 with screen bottom...Or do you just have 4 bins and hand separate as needed.. Or just let them do there thing in same bin
I separate some but for the most part I let them go . I find that The four will supply me just adding wheat bran .
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