A TDS Pen enables you to test the quality of various sources of water, including your aquarium water and reverse osmosis water, which is an essential part of shrimp keeping.
This pen provides up to 1000 hours of continuous usage. It also includes an accurate and built-in thermometer.
The hold button is aimed at saving measurements for convenient reading and recording. It also has an auto-off function, which can turn off after 5 minutes of non-use to conserve batteries.