what to use for lid, weight, on fermenting crock?

We moved into a 100 year old farm house and I found a crock in the cellar. Since I have never fermented anything in my life I didn't know what it was for. I can't find a lid or weight or anything else that seems to go with the crock. It is about the size of a 5 gallon bucket. I can't wait to ferment something in this crock but what should I use for a lid and a weight?

generally a clean plate that will fit inside the top fairly snugly and a clean rock are used for a lid and weight

Thank You Brenda. So, I just put the plate inside the crock and the rock over the plate? Sorry to ask stupid questions but I am new to this and don't want to get it wrong.

One more newbie question....what is the difference between fermenting and lacto-fermenting?

Fermenting, in general, refers to processing foods using micro-organisms. Yeast feed on sugars produces alcohol as a byproduct. Lacto-bacilli produce lactic acid. Acetic acid bacteria (acetobacters or acetobacilli) produce acetic acid: vinegar.

Fermenting is the broad category that covers at least three kinds of fermentation. Those are categorized by what is produced: alcohol, vinegar or lactic acid.

Lacto-fermented means the organisms involved produce lactic acid.