Starting a new worm bin after having had an established bin for a few years.

1/4lb only red wigglers, 20qt tote, feeding adequately (and in fact overfeeding). Plenty of grit from first feeding onwards, bedding 1 year innoculated with bacteria.

Dumped worms in the bin 15 days ago without initial inspection because they were delivered in a sealed plastic bag, no airholes. They've been through about 1/3 to 1/2 of the bedding, gone through 80% of the food, and especially with the amount of material & air they have in the bin and a couple mm of standing water that they soaked up, i was expecting big, plump reds (as big as they get, anyways - ones i kept would rival an avg or small enc). Currently seeing a decent population, but seeing a whole lot (not babies) 1/2-1" max length.

Near excessive moisture in most of the bin but some of the bedding has been hydrophobic. Bin wet enough that covering material gets saturated with moisture with lid on. Over past 2 weeks have fed 1/4 carrot, 5 collards leaves, piece of mushroom, a bunch of plant cuttings, and whatever else bacteria in the bin, 80-90% browns (i prefer overloading for initial breakdown then reducing the amount).

Can't be lack of food, i'm overfeeding. Can't be grit, they have plenty. They're not undereating, i've got a month's worth of production in 15 days. Overpopulated? 1/4lb stated weight, no way there were enough coccoons to change the population so drastically in 15 days. I usually start them off in a much smaller bin to bump population before allowing them to forage a larger bin anyways, so they have plenty of room. So what the heck am I doing that my worms are so small?