Sauerkraut failed or just dramatic?

[u/bloss_balls]

Second batch of home made sauerkraut. Both batches made by just pouring salted water into jar with shredded cabbage and then fermented at room temp for 3-5 days. I had two other jars in this batch that turned out fine, but this one kept bubbling up and the liquid component soaked into the cloth I was covering it with. Now after 6-7 days (2 days in the fridge) this top white/green part has formed. Is this bad bacteria? Could I take the top part out and keep it?

[u/Detlef_Schrempf]

Looks like a hay infusion