Refractometer VS Hydrometer

[ericscicluna]

Hi Guys,

What shall I use to test the proper salinity in my water ? A refractometer or a Hydrometer ... OR BOTH ?

And what is the main difference ? Is it just accuracy ?

Thanks a lot
Eric

 

[bang guy]

A Hydrometer measures the density of the water. If you combine that with a temperature reading and a Salinity chart you can derive the Salinity.

A Refractometer measures the light refraction index which can directly derive the Salinity of the water using the built in refraction index.

A Conductivity meter measures how easily electricity flows through the water which also can directly derive the Salinity.

The most accurate is the Conductivity Meter followed closely by the Refractometer and way behind is the Hydrometer. Hydrometers can actually be sufficient but due to manufacturing issues they can be inconsistent.

For the average hobbyist I would recommend a refractometer because you can directly read the Salinity without having to know the water temperature.

 

[ericscicluna]

Quote:
Originally Posted by Bang Guy http:///t/397084/refractometer-vs-hydrometer#post_3538261
A Hydrometer measures the density of the water. If you combine that with a temperature reading and a Salinity chart you can derive the Salinity.

A Refractometer measures the light refraction index which can directly derive the Salinity of the water using the built in refraction index.

A Conductivity meter measures how easily electricity flows through the water which also can directly derive the Salinity.

The most accurate is the Conductivity Meter followed closely by the Refractometer and way behind is the Hydrometer. Hydrometers can actually be sufficient but due to manufacturing issues they can be inconsistent.

For the average hobbyist I would recommend a refractometer because you can directly read the Salinity without having to know the water temperature.

Thanks alot for your helpful reply !!! So the best way is to get them both right ?? So that i'll be accurate and be sure about calibration issues ??

 

[bang guy]

All you really need is a refractometer. If you get one that comes with calibration fluid you'll know the accuracy for sure but for hobby purposes close is good enough as long as it's consistent.

 

[flower]

Quote:
Originally Posted by Bang Guy http:///t/397084/refractometer-vs-hydrometer#post_3538330
All you really need is a refractometer. If you get one that comes with calibration fluid you'll know the accuracy for sure but for hobby purposes close is good enough as long as it's consistent.


Hi,

LOL...The professors have spoken...but I want to add my opinion.

The last of what Bang Guy said is the key to the whole thing....close is good enough, as long as it's consistent.

You only need one or the other, not both. LFS do not sell refractometers, I have only been able to purchase them on-line. I paid $50.00 for my refractometer...it's a cheap one. The average hydrometer runs between $6.00 and $10.00

A refractometer is very accurate, an hydrometer, not so much. However, if you are only using your hydrometer to make sure your water change water is the same reading as the tanks water or that the tanks water parameters are in range...it's good enough. Even if the hydrometer is off, as long as it matches the tanks water on the same device...you are good to go.

If you ever get the ich parasite and need to do the hyposalinity treatment Beth recommends...you MUST use a refractometer, because when you do hypo...close is not good enough.

As to which is best, it just makes sense, if you can afford it, to get the best right off...why shoot for good enough, when you can have accuracy?

I'm adding this just for educational purposes, for all who read this post....The reason we want to make sure the numbers match:
Sea critters come from the ocean, where things are very, very stable and change if it ever happens, happens very, very slowly. Our fish tanks can change on a dime, but our sea friends have not had to adjust to sudden changes for centuries. It's kind of like the bubble babies, they can't be exposed because their bodies can't handle it, even a little cold germ could kill them. In the same way, a sudden change can kill our critters.

 

[ericscicluna]

Quote:
Originally Posted by Flower http:///t/397084/refractometer-vs-hydrometer#post_3538332


Hi,

LOL...The professors have spoken...but I want to add my opinion.

The last of what Bang Guy said is the key to the whole thing....close is good enough, as long as it's consistent.

You only need one or the other, not both. LFS do not sell refractometers, I have only been able to purchase them on-line. I paid $50.00 for my refractometer...it's a cheap one. The average hydrometer runs between $6.00 and $10.00

A refractometer is very accurate, an hydrometer, not so much. However, if you are only using your hydrometer to make sure your water change water is the same reading as the tanks water or that the tanks water parameters are in range...it's good enough. Even if the hydrometer is off, as long as it matches the tanks water on the same device...you are good to go.

If you ever get the ich parasite and need to do the hyposalinity treatment Beth recommends...you MUST use a refractometer, because when you do hypo...close is not good enough.

As to which is best, it just makes sense, if you can afford it, to get the best right off...why shoot for good enough, when you can have accuracy?

I'm adding this just for educational purposes, for all who read this post....The reason we want to make sure the numbers match:
Sea critters come from the ocean, where things are very, very stable and change if it ever happens, happens very, very slowly. Our fish tanks can change on a dime, but our sea friends have not had to adjust to sudden changes for centuries. It's kind of like the bubble babies, they can't be exposed because their bodies can't handle it, even a little cold germ could kill them. In the same way, a sudden change can kill our critters.
Thanks a lot for your replies much appreciated... I'm getting a refractometer

 

[tur4k]

Quote:
Originally Posted by Flower http:///t/397084/refractometer-vs-hydrometer#post_3538332
LFS do not sell refractometers, I have only been able to purchase them on-line.



I bought my refractometer at my LFS. They actually had a pretty decent selection. I personally will never use a hydrometer again. Bubbles have a nasty habit of sticking to the needle of cheap plastic hydrometers. This throws the reading way off. You're much better off spending a little extra $$ and getting a decent refractometer.

 

[jay0705]

Agreed refract is the way to go. I could not believe how off my hydrometer was

 

[siptang]

I go with Milwaukee digital refractometer and I haven't looked back since.
Sent from my SM-N900P using Tapatalk

 

[ecooper]

Quote:
Originally Posted by tur4k http:///t/397084/refractometer-vs-hydrometer#post_3538563



I bought my refractometer at my LFS. They actually had a pretty decent selection. I personally will never use a hydrometer again. Bubbles have a nasty habit of sticking to the needle of cheap plastic hydrometers. This throws the reading way off. You're much better off spending a little extra $$ and getting a decent refractometer.
+1