It's my first time posting on this forum and I come to you with a sauerkraut question. I am on day three of fermenting in small fido jars, and noticed that my cabbage is not fully submerged under the liquid. Is it safe to open the jars to tamp down the cabbage and add some water so that they are covered? I am not using fermentation weights. I'm attaching a photo so you can see what I mean. I am scared about introducing oxygen to the kraut if I open up the jars, but I know that I risk molding if the kraut is not submerged. Any advice helps!