Storage keeps filling up

I have an issue currently whereby, after purging and restarting, the 8gb of free space is used up within an hour or so.

The main suspect is some node-red flows I had been working on. One was reading in emails that contained video attachments. There were a dozen or so emails and I had been playing with reading all emails, not just unseen, and had deployed these at some points.

I decided to work on node-red outside of HA so that I had less chance of space issues, so deleted all the flow nodes in HA Node-red.

I thought this would ensure nothing was still running. Is it possible that, although no nodes remain in the node-red flows, that deployed versions are still running in the background?

How can I identify what is using up my 8gb if space?