- Accurate Water Quality Measurement: The TDS test pen delivers precise readings of total soluble solids in water (0-9999ppm). This makes it essential for monitoring water quality in drinking water, aquariums, and agricultural applications. - Versatile Applications: Ideal for use in coral and fish farming, fertilizer adjustments, and filter testing. This tester enables you to track water quality in real time, allowing for prompt actions to ensure the health of your plants and fish. - User-Friendly Features: Constructed with a waterproof IPX6 housing and a durable titanium alloy probe, the TDS test pen is built to last. The clear digital LED screen displays results in an easy-to-read format, providing instant feedback on water quality. - Energy Efficient & Portable: Designed with an energy-efficient microprocessor and compact dimensions (15 x 1.6 x 1.6 cm), this water quality test pen is convenient for home use or travel. It comes with two AG13 button batteries for extended operation. - Practical Use Cases: - Regularly check the TDS levels in your drinking water to ensure safety and quality. - Monitor aquarium water quality to maintain a healthy environment for fish and coral. - Adjust fertilizer levels in your garden by measuring water quality before application.