Hydrometer

I had one of these hydrometer/thermometers

Aquatic Gardens Aquarium Hydrometer with Thermometer at PETCO

I was wondering if its any good it seems to be accurate but I was just wondering what your guys thoughts are on it.

Thanks alot

 

I have used one for years with no problems in fact i have 3 of them and check them against one another but a refractometer is more accurate.

 

I've had no problem with mine. It's a very economical product.

 

A properly calibrated refractometer is going to be more accurate across a broad range of conditions period. A hydrometer will change readings based on temp, condition, salt buildup, ect.
I understand that there are many places to save money in this hobby, but as far as I am concerned with a refractometer easily available for $40 or less there is *no* reason to not pick one up.

 

the key words

 

a hydrometer displays both salinity and specific gravity. they say they do not need correction for temperature as the plastic that the pointer is made from is designed to change its density with temperature at the same rate as seawater but a refractometer is also more accurate....."properly calibrated"

 

The same goes for a hydrometer. The difference is once you have established a baseline the accuracy is going to be worlds and away different. In my experience hydrometers tend to average .003-.005 below what they should.
Calibrating a refractometer is a simple matter of a test solution where as a hydro you have zero clue what cleanliness and salt buildup is actually doing.

 

I let the store spend the big bucks and use the cheap plastic one. I check mine against theres and its a few below. But it doesnt need to be calibrated either. makes sense to me. haha

 

If its a few below and is known to be inaccurate what does testing with it accomplish?

 

ill always know im just 3 below where im suppose to be long as i keep it clean doe