What limits the amount of water on earth? Or the depth of the ocean when measured from the top?

I’m thinking the answer is as simple as there just being a finite amount of water on earth?

I guess my question is, why can’t the earth grow in size? In terms of more water I mean. What’s stopping the oceans from getting deeper, and covering up land masses. What sets ocean levels to a set point that allows for land masses to be above it? I know with melting glaciers, water levels will rise, but is there a set level to that? If all frozen ice on earth melted, wouldn’t earth technically be larger in diameter? I know that’s multiple questions, but it’s just something I’ve been wondering.