Refractometer or Hydrometer?
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Ryan15236
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Everyone recommends a refractometer usually. It is a good thing to have. However, I rarely pull mine out. Most of the time on my Friday testing routine I just dip the hydrometer in the tank, give it a few good taps to ensure no air bubbles on the swinging arm and I get a pretty accurate read. Always get the same with my refractometer and hydrometer. I think where a lot of people may mess up is the cleanliness of their testing equipment. Just like you would for any kind of lab work whether it be in a college chemistry course or for a chemical company. Cleanliness is very important. I rinse my hydrometer before use. Shaking it a bit to make sure the swinging arm is swinging freely and then dip in the tank. Followed by another rinse before storage.
OP
OP
Aliu
Community Member
Thanks for the advice Ryan. I'm an avid scuba diver so I definitely agree with you on the maintenance of your equipment. I always rinse my equipment before and after every dive. Have to be able to maintain good condition for everything. Looks like they are both similar just depends on what you like to use better.
Ryan15236
Active Member
No problem! Good luck! Also don't get me wrong. A refractometer will always be more reliable and precise if calibrated correctly. Refractometers take away the reliance on moving parts which would make the refractometer more reliable. I am not sure I would recommend a hydrometer only. Especially for reefs where we want a precise and consistent salinity. I am just stating I use my hydrometer a lot more frequently. Best of luck!
Blue Lip
Well-Known Member
A hydrometer is actually temperature sensitive. Most people use rodi water to mix their salt. Freshly made rodi water is typically cold. A refractometer is not temperature sensitive. See where im going with this?
Ryan15236
Active Member
Great point! I would always recommend letting your freshly mixed ro/di saltwater sit overnight with heated to tank temp with some circulation then measuring the salinity and adjusting a necessary before a water change if you go the hydrometer route.
What kind of hydrometer?
FWIW, I've been using a cheap floating glass hydrometer for the past 17 years or so without any problems. My parents used to use the same thing back on their tank back in the late 70's early 80's as well. Also, like mentioned above temperature can be an issue with a hydrometer, but this is a quick fix. The water doesn't have to be 78 degrees everytime to get an accurate reading. There's a safety zone so to say.
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Oceansize
Active Member
I think the only reason to go with a hydrometer over a refractometer would be if you're on a tight budget. The refractometer is superior in every way, but that is not to say that a hydrometer will necessarily lead you wrong. I'm one of those "buy right or buy twice" people so I figure why risk it, and thus use a refractometer.
FWIW, I do not have air conditioning and both my tank and room temp have experienced some pretty significant temperature changes over the summer, which would be a case for using a refractometer instead of a hydrometer: for maximum accuracy you want to use something that can account for temperature differences versus where they were when the device was calibrated. Refractometers (specifically ATC (automatic temperature control) refractometers) take care of this for you. Hydrometers do not. Who knows if you'd ever notice a difference, but better to be safe than sorry.
FWIW, I do not have air conditioning and both my tank and room temp have experienced some pretty significant temperature changes over the summer, which would be a case for using a refractometer instead of a hydrometer: for maximum accuracy you want to use something that can account for temperature differences versus where they were when the device was calibrated. Refractometers (specifically ATC (automatic temperature control) refractometers) take care of this for you. Hydrometers do not. Who knows if you'd ever notice a difference, but better to be safe than sorry.
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RobBaglieri
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Best investment I ever made is my Milwaukee Refractometer. Hydrometers need to be very clean and be an a perfectly level surface to get good results. Also, there is no temperature compensation with hydrometers.
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I prefer conductivity.
Of course you do.
I prefer to get on a plane to the tropics with my $5.00 swing arm hydrometer, take a boat out to where they collect my fish, jump in the water and test it. Draw a line on the thing where the arm stops. Then I get on a plane, go home and set my water to where it was in the tropics. Easy and only cost $8,000.00.
You can do the same thing with a refractometer but then it will cost you $8,0120.00
Mandrew
Well-Known Member
Of course you do.
I prefer to get on a plane to the tropics with my $5.00 swing arm hydrometer, take a boat out to where they collect my fish, jump in the water and test it. Draw a line on the thing where the arm stops. Then I get on a plane, go home and set my water to where it was in the tropics. Easy and only cost $8,000.00.
You can do the same thing with a refractometer but then it will cost you $8,0120.00
That's hilarious! I thought it was a joke until I seen the picture lol
Brew12
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Of course u doI prefer conductivity.
Haha
RobBaglieri
Active Member
I use the floating type when making beer. Never thought of using it in a tank.
stevo01
R33F!N @DD!CT
I started with a hydrometer as I was accustomed to using one for brewing beer. Turned out to be a completely different style of hydrometer that what I use for beer. I use an ATC refractometer now. I feel it's more reliable, and you save on tank water.
