Description
xOverview
The HI783-25 Marine Magnesium Checker Reagents are replacement reagent sets designed for Hanna’s Marine Magnesium Checker HC (HI783). Each packet is pre-measured, making magnesium testing faster and more consistent. They are manufactured in Hanna’s facility using high-purity chemicals and are clearly labeled with lot numbers and expiration dates to support traceability across testing sessions.
How the test works
These reagents use a colorimetric EDTA method with a calmagite indicator. When magnesium from your seawater interacts with the reagent, the solution shifts from blue to violet. The resulting color intensity corresponds to a magnesium concentration expressed in parts per million (ppm) when read with the HI783 instrument or referenced against the color guide.
Designed for seawater ranges
HI783-25 reagents are optimized for saltwater samples with an expected magnesium range of roughly 1,000 to 1,800 ppm. Using them with the Marine Magnesium Checker HC helps you compare your readings to common marine aquarium targets and maintain stable water chemistry over time.
What you get
- Pre-made reagents for ease of use
- Prepared with high purity chemicals
- Marked with expiration date and lot number for traceability
Why this matters for hobbyists and professionals
- Fast, reproducible results with minimal preparation
- Clear color change helps readings in low-light or busy tanks
- Lot-based traceability supports consistent testing across sessions
Real-world use cases
From reef tanks to mixed ecosystems and quarantine displays, HI783-25 reagents provide a convenient option for monitoring magnesium. They pair with the HI783 reader to deliver data you can log over time, helping you observe trends and adjust practices as needed.
Quality and handling
Manufactured to high standards and clearly labeled for traceability, these reagents are designed to support ongoing maintenance without requiring extensive preparation. Store in a cool, dry place and use before the indicated expiration date to ensure accuracy.
FAQ
Q: What is HI783-25 used for?
A: HI783-25 are replacement reagents for the Marine Magnesium Checker HC, pre-measured for quick, reliable magnesium testing in seawater.
Q: What range is HI783-25 designed for?
A: They are optimized for 1,000 to 1,800 ppm magnesium in saltwater samples when used with the HI783 instrument.
Shipping & Return
xReturns Policy
You may return most new, unopened items within 30 days of delivery for a full refund. We'll also pay the return shipping costs if the return is a result of our error (you received an incorrect or defective item, etc.).
You should expect to receive your refund within four weeks of giving your package to the return shipper, however, in many cases you will receive a refund more quickly. This time period includes the transit time for us to receive your return from the shipper (5 to 10 business days), the time it takes us to process your return once we receive it (3 to 5 business days), and the time it takes your bank to process our refund request (5 to 10 business days).
If you need to return an item, simply login to your account, view the order using the "Complete Orders" link under the My Account menu and click the Return Item(s) button. We'll notify you via e-mail of your refund once we've received and processed the returned item.
Shipping
We can ship to virtually any address in the world. Note that there are restrictions on some products, and some products cannot be shipped to international destinations.
When you place an order, we will estimate shipping and delivery dates for you based on the availability of your items and the shipping options you choose. Depending on the shipping provider you choose, shipping date estimates may appear on the shipping quotes page.
Please also note that the shipping rates for many items we sell are weight-based. The weight of any such item can be found on its detail page. To reflect the policies of the shipping companies we use, all weights will be rounded up to the next full pound.
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