The hardest part is getting your head around InfluxDB and configuring some sensible data. I know I posted some guidance on that quite a long time ago. You do also need to keep your InfluxDB databases to sensible sizes as well, especially on a Pi.
How to effectively use InfluxDB - FAQs - Node-RED Forum (nodered.org)
But InfluxDB has some built in features for trimming DB's but also for aggregating data. For example, I keep my once-per-minute sensor data for a week but also aggregate to hourly data as I go along and keep the hourly data (with min/max/avg data points) for a few years. InfluxDB has features for automating all of that.
