All of my chickens have had very watery, splashy pooh for weeks now. What could this be?

I have 33 adults ranging from 1-5 years old. Back in Nov. they went from 20+ eggs a day to 1-2 a day. Figured it was from the temps. dropping, shorter days, and some of them seemed to be molting. Their production has picked up to about a dozen a day now but I have noticed for a few weeks now that they are all having splahy, watery poop. Almost never see solids anymore. They eat only layer pellets and table scraps when available. They seem normal in behavior but I figure they can only go so long like this befor their health starts to suffer. Whenever I walk in the hen house at night to check on them and get any late eggs, I can hear splashing constantly.
Anyone have any idea what this could be and what I need to treat it?

 

Didn't think worms would make them like that, but no not lately.

 

They seem fine and I have not noticed any weight loss. Even the ones that looked like they were molting are now looking really pretty.
I have heard of some wormers that did not require that the eggs be tossed. Any idea where I could fine one like that?