Refractometer vs Hydrometer

The friendliest place on the web for anyone with an interest in aquariums or fish keeping!
If you have answers, please help by responding to the unanswered posts.

Animal-Chin

Aquarium Advice Addict
Joined
Nov 8, 2011
Messages
1,315
Location
Vancouver BC
just learned my lesson. i had a hydrometer for years to test my salt level and it seemed to work fine. few weeks ago it broke so i bought another one by a different company. i used it to measure my salinity for the water i use for water changes and would mix my water to 1.025 for each change. well turns out my $10 hydrometer was crap and I was actually raising my salinity constantly and slowly with each change until I was at 1.029 in my aquarium. I had a feeling something was off so i purchased another hydrometer that was showing my salt at 1.030 so I had a .05 difference between them. Stressed out i purchased a refractometer and now I get accurate readings every time!

Spend the extra $40 the first time and get the proper tool. I spent $30 in total on crappy plastic floats when I could have just caughed up the $50 the first time and did it right. I'm finally confident i'm gettign proper readings and I'm bringing my salt back down to the 1.025 i like to keep it at.

Plus refractometers feel like a real tools and are fun to use...lol

luckly all i lost while raising my salinity were some snails and crabs. All coral and fish lived through the screw up...
 
One quote I'll never forget from my photo-journalism teacher (many years ago)..... "If you buy the good stuff, you only cry once...."
 
One quote I'll never forget from my photo-journalism teacher (many years ago)..... "If you buy the good stuff, you only cry once...."

+1, have always believed you get what you pay for

A refractometers really needs to be one of the first pieces of equipment that you buy, after all your fish and corals live in the water you are testing. We spend thousands on equipment, but then get the cheapest equipment we can get to test the water they live in.
 
Holygral said:
+1, have always believed you get what you pay for

A refractometers really needs to be one of the first pieces of equipment that you buy, after all your fish and corals live in the water you are testing. We spend thousands on equipment, but then get the cheapest equipment we can get to test the water they live in.

+1 I've got way to much money tied into this hobby to trust a little plastic hydrometer haha. One of the first things I tell new salties is don't get the hydrometer, do it right the first time and buy a refractometer :)
 
My LFS uses hydrometers and all his tanks are amazing and his personal 500g reef is out of this world he has been a reefer for 30 plus years and he manages a ton of tanks and is extremely knowledgeable so I tend to take his advice
 
and there are many people on here who have out of this world tanks that use refractometers, so what does that prove? And they are not trying to sell you anything. It is a known fact that hydrometers as used are inaccurate. They must be rinsed in RODI and dried after each use, and then there is no guarantee. A refractomer is very accurate and can be calibrated with a drop of calibration fluid and then you know it is accurate. How do you calibrate a swing arm. Take 3 swing arms and they will all give you different results of the same water, if a refractometer is calibrated they will all be the same.
 
MyR6Rocks said:
Are all refractometers created equal? Seems to be quit a range online.

Kinda. Some are different kinds of measurements but as far as I know all refractometers for home aquaria are very accurate. As stated above you can always check your accuracy with your calibration fluid so that there is no questioning it.
 
as long as you calibrate them, I would stay away from ebay cheapos and buy from a reputable store incase you have a problem. Only difference I have found over the years is the blue background that you read against, some of them are dark blue which means you need stronger light to read, the light blue ones are best if you can find them. You can only tell from the pictures, they don't specify the shade. They need to be calibrated with calibration fluid not rodi water. Rodi water will get them close but the reason we buy them is for accuracy.
 
Holygral said:
as long as you calibrate them, I would stay away from ebay cheapos and buy from a reputable store incase you have a problem. Only difference I have found over the years is the blue background that you read against, some of them are dark blue which means you need stronger light to read, the light blue ones are best if you can find them. You can only tell from the pictures, they don't specify the shade. They need to be calibrated with calibration fluid not rodi water. Rodi water will get them close but the reason we buy them is for accuracy.

So I ordered 1 online for $50, and according to the picture the background is light blue so hopefully it's a good one. Just have to find "calibration fluid" now.
 
So I ordered 1 online for $50, and according to the picture the background is light blue so hopefully it's a good one. Just have to find "calibration fluid" now.

Just do a search, you can get it anywhere on the web, the dark blues work just as well, I just prefer the lighter backgrounds. I use pinpoint fluid, a little goes a long way.
 
Holygral said:
Just do a search, you can get it anywhere on the web, the dark blues work just as well, I just prefer the lighter backgrounds. I use pinpoint fluid, a little goes a long way.

Thanks for the input. Very helpful
 
Back
Top Bottom