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Hanna Instruments Hanna Marine Magnesium Checker HC HI783 Saltwater Aquariums, Marine, Aquaculture Applications Magnesium Tester 64 grams

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Availability: 11 left in stock
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Arrives Thursday, May 7
Order within 10 hours and 34 minutes
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Features

  • Fewer steps than other chemical tests
  • Color-coded syringes make the magnesium test simple and effortless
  • Dedicated to a single parameter
  • Small size, big convenience
  • Ideal for: Saltwater Aquariums, Marine, and Aquaculture Applications

Description

Our Marine Magnesium Checker HC (HI783) is designed to accurately and quickly determine the magnesium level in marine (saltwater) samples. The digital readout makes measurements effortless. Our Magnesium Checker HC (HI783) is the first marine magnesium test of its kind! This Checker provides an uncomplicated, accurate, and budget-friendly way to measure magnesium in saltwater/marine environments. Color-coded syringes and straightforward testing steps ensure quick and easy measurements every time! Magnesium is vital in saltwater environments as it allows calcium and carbonate to be bioavailable for corals and invertebrates. Designed as a more accurate alternative to chemical test kits, our Marine Magnesium Checker HC (HI783) provides quick, accurate results in a few easy steps. Magnesium Checker Tips & Tricks for Accurate Measurements Measure liquids accurately by syringe by drawing up the plunger until the bottom seal of the plunger is at the desired volume mark. Do NOT raise the liquid to the mark as this will give a false high volume. An air gap between the plunger and liquid is normal. Always use clean, dry cuvettes and syringes/tips. Rinse with deionized (RODI) water only; never rinse with tank water. Dry the cuvettes before use to prevent dilution. Ensure the sample does not contain any debris. Whenever the cuvette is placed into the checker, it must be dry outside and free of fingerprints, oil and dirt. Wipe the cuvette thoroughly with HI731318 microfiber cleaning cloth or a lint-free cloth prior to insertion. Shaking the cuvette can generate bubbles, causing higher readings. To obtain accurate measurements, remove such bubbles by swirling or by gently tapping the cuvette. Do not let the reacted sample stand too long after reagent has been added, as accuracy will be affected. Discard the sample immediately after the readng has been taken or the glass might become permanently stained. Keep the tips with their appropriate syringes during measurement.

Brand: Hanna Instruments


Liquid Volume: 5 Milliliters


Item Weight: 0.59 Kilograms


Item Form: handheld


Unit Count: 1.00 Count


Package Dimensions ‏ : ‎ 9.21 x 6.5 x 2.6 inches; 1.3 Pounds


Date First Available ‏ : ‎ June 2, 2022


Manufacturer ‏ : ‎ Hanna Marine Magnesium Checker® HC HI783


Best Sellers Rank: #28,939 in Pet Supplies (See Top 100 in Pet Supplies) #43 in Aquarium Test Kits


#43 in Aquarium Test Kits:


Customer Reviews: 4.3 4.3 out of 5 stars (253)


Brand Name: Hanna Instruments


Manufacturer: Hanna Marine Magnesium Checker® HC HI783


Unit Count: 1.00 Count


Liquid Volume: 5 Milliliters


Item Weight: 0.59 Kilograms


Item Form: handheld


Target Species: Fish


Frequently asked questions

If you place your order now, the estimated arrival date for this product is: Thursday, May 7

Yes, absolutely! You may return this product for a full refund within 30 days of receiving it.

To initiate a return, please visit our Returns Center.

View our full returns policy here.

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Top Amazon Reviews


  • Test every other day.
This is a easy test with Hanna just read the instructions.
Reviewed in the United States on April 1, 2026 by Doug

  • Much better results than color chart tests
Works great and much easier than the color chart tests. The liquid reagent though is very sticky and challenging to clean up if you spill it. I started pouring it into a glass before using the syringe. Not easy to use packaging in that part.
Reviewed in the United States on May 1, 2026 by Chris Thomas

  • Good Magnesium Checker
This one was a little more involved than the alk, PO4 and NO3 checkers but still easy enough to use and great to have a number instead of guessing on standard tests. Helps to gauge when to add more Mg to the system.
Reviewed in the United States on August 8, 2025 by Bonnie Boe

  • Save your money, many cheaper, easier to use tests kits exist from other manufacturers.
Have the Hanna alkalinity tester and it works like a charm everytime. The Magnesium tester is a piece of junk. The process to test is way to involved, any extremely slight miscalculation of any of the three samples skews the results greatly. Also, the corvette supplied do not securely attach to the syringes supplied so it is fairly impossible to even get an accurate reading on the doses. Save your money, by a different brand if test kit for Magnesium. ... show more
Reviewed in the United States on April 2, 2026 by Frank

  • worth it
easy to use
Reviewed in the United States on January 9, 2026 by Amazon Customer

  • Worked great
Worked great
Reviewed in the United States on October 7, 2025 by Shane Walmsley

  • Great Product
Great Product
Reviewed in the United States on August 17, 2025 by Luis Morales

  • I love it
Works great and gives accurate reading.
Reviewed in the United States on March 14, 2025 by Steve Rotter

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