Review Details

Boxtech Aquarium Marine Test Hydrometer for Fresh Water and Sea Water

Product Review (submitted on December 16, 2021):

If you are new to these, pay attention. Bubble will form on the float and they need to be shaken off (very easy). Do NOT install this in your tank or it will grow algae on it.
How to use properly:
1. Fill with water, knock against tank to take off bubbles.
2. Repeat step 1 like 5 times
3. Fill with water and read.

This is calibrated at 77 degrees F or 25 degrees C. If you have cold water fish (under 25C) use google.com to find the conversion tables. it is not much of a difference, but if you are keeping very cold water expensive corals and fish... 'mightcould want to check it out.