> For the complete documentation index, see [llms.txt](https://faq.growsensor.co/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://faq.growsensor.co/substrate-probes.md).

# Substrate probes

{% content-ref url="/pages/jjloWYQAxuVDD4uBcHiI" %}
[What soil probes are compatible with the Grow Sensor?](/substrate-probes/what-soil-probes-are-compatible-with-the-grow-sensor.md)
{% endcontent-ref %}

{% content-ref url="/pages/CYbFvVKGRRdEmUOovOKL" %}
[Which sensors should I purchase?](/substrate-probes/which-sensors-should-i-purchase.md)
{% endcontent-ref %}

{% content-ref url="/pages/NmkZQ6VKKDj5meJwn8ry" %}
[What do the substrate probes measure?](/substrate-probes/what-do-the-substrate-probes-measure.md)
{% endcontent-ref %}

{% content-ref url="/pages/YahZHG4KZmpA0BRnO6VR" %}
[Can I change my substrate type in the Grow App?](/substrate-probes/can-i-change-my-substrate-type-in-the-grow-app.md)
{% endcontent-ref %}

{% content-ref url="/pages/dhLKbwlFNmYzvb9X43Ah" %}
[How do I connect a substrate probe to the Grow Sensor using the SDI-12 connector block?](/substrate-probes/how-do-i-connect-a-substrate-probe-to-the-grow-sensor-using-the-sdi-12-connector-block.md)
{% endcontent-ref %}

{% content-ref url="/pages/26Hylqj8TVb0oJPRV8RK" %}
[How many substrate probes can I use with the Grow Sensor?](/substrate-probes/how-many-substrate-probes-can-i-use-with-the-grow-sensor.md)
{% endcontent-ref %}

{% content-ref url="/pages/AKXT2N1NSn3BIwKMi1eR" %}
[How do I position my soil probe for my pot size?](/substrate-probes/how-do-i-position-my-soil-probe-for-my-pot-size.md)
{% endcontent-ref %}

{% content-ref url="/pages/6DxZOddR9eU69nfPnKwN" %}
[My VWC reading is too low or high, help!](/substrate-probes/my-vwc-reading-is-too-low-or-high-help.md)
{% endcontent-ref %}


---

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