Can someone please help me figure out what I've done wrong with this wither skeleton grinder/farm? I have no idea where the items go when the skeletons die as they're not ending up in the chests and skeletons keep spawning outside the farm for some reason.
My computer isn't letting me see the image, but do you have hoppers directly over the chests? Maybe you should put more chests around it with hoppers too, just in case the items are missing the chests.
Do you have a stream of water coming from the spawn room to the hopper? It needs that to move the items.
Also, you could try making the farm slightly bigger to stop skeletons spawning outside.
The hoppers are directly over the chests, but I also have item filters to sort the items. I'm literally watching the hoppers pick up the items, but then they just disappear. I have no water over the hoppers as the server I'm building this for periodically clears items that aren't in hoppers or chests or whatever.
I figured out that one of the main hoppers was receiving a redstone signal thus locking it. But now the non-stackable item filter isn't working. It's letting stackable items get into the dropper below it.