How long HydroNode keeps your sensor data

Choose per sensor how long readings are kept: 7, 30, 60, 90 days or a year. What is deleted at night, what stays, and which period fits your sensor.

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The Keep readings setting of a sensor with the choice from 7 days to 1 year openThe Keep readings setting of a sensor with the choice from 7 days to 1 year open

Every sensor now has a retention period of its own. You choose how long HydroNode keeps its readings: 7, 30, 60 or 90 days, or a year. Without a choice it is 30 days. Whatever is older, HydroNode deletes every night. Here is what exactly goes, what stays, and which period fits which sensor.

Set it

  1. Open the settingsOn the sensor page press Settings at the top right, then General.
  2. Pick the periodAt the bottom, under Keep readings, is How long readings are kept. Pick 7, 30, 60, 90 days or 1 year.
  3. SaveThe bar with Save changes shows at the bottom. A shorter period asks first, because deleted readings do not come back.
The Keep readings group in the sensor settings with the choice from 7 days to 1 year openThe Keep readings group in the sensor settings with the choice from 7 days to 1 year open
One setting per sensor. Only the owner can change it.

What happens every night

  1. ReadingsArrive and are stored
  2. KeptFor the period you chose
  3. NightOlder ones are deleted
  4. ChartsSummaries follow
It deletes in small batches, so your sensor never gets slower while it runs.

At night HydroNode deletes every reading older than the period you chose. The values calculated from them go with them, such as dew point or VPD, and so do the summaries long charts are drawn from. With a lot of old readings this takes a few nights, because HydroNode deletes only so much per night.

DeletedReadings, calculated values and chart summaries older than the period.
StaysSensor, station, shares, settings, anomalies and AI analyses.
Own limitsThe console keeps its lines for 48 hours, messages stay 30 days.
Gone at onceDeleting the sensor or your account removes its readings right away.

Which period fits

PeriodFits
7 daysTest setups on the desk and devices where only the current value counts.
30 daysThe default. Enough for charts, alerts and anomaly detection with the full daily pattern.
60 or 90 daysGreenhouses, grow cycles, water tanks: anything you follow through a season.
1 yearWeather stations and rooms you want to compare with last year.
Anomaly detection Detection learns from at most four weeks of hourly values. With 30 days or more nothing changes for it. With 7 days it learns from that one week only. That is enough for the daily pattern, but the expected band rests on fewer days.

Sensors from before

For sensors that existed before this setting, HydroNode deletes nothing for the first 30 days. A message lands in your inbox, and when readings would be lost, a mail follows seven days before the end. Below the choice it says until when nothing goes. To keep more than 30 days, pick a longer period in that time and no reading is lost.

Calculated values and the past

When you switch a calculated value on, HydroNode calculates it for the last 30 days. Never further back than the sensor keeps its readings: with 7 days it is 7 days. How that runs is in Calculate dew point and VPD.

The window The last 30 days are calculated with 16,758 values for dew point and VPDThe window The last 30 days are calculated with 16,758 values for dew point and VPD
After saving, HydroNode calculates day by day, at most as far back as the sensor has readings.

Where to go next