Thanks, Daniel!
This is a good place to be - and the best place to gather information in an effort to solve aquaristic issues.
Speaking of which, and for the benefit of any future readers ... My "Instant Ocean" swing-arm hydrometer (I know - swing-arm hydrometers - but there are times that I just don't want to go through the rigamarole of pulling out the refractometer to get a ballpark on salinity, and this one had always been pretty accurate...) got so busted up that I decided to replace it. The most-local shop (Petco) was out of the Instant Ocean version, so I grabbed a "Fluval Sea" swing-arm off the peg.
Don't do what I did. Just ... don't.
The Fluval Sea swing-arm hydrometer has two readings. In fresh water, the needle rests on the bottom of the hydrometer. If there's any salt at all in the water, the needle will rise to the surface of the water within the unit. It's about as useful as throwing a rock at a chart. This model has a suction cup to attach it to the front glass of the aquarium, which puzzles me for two reasons. 1 - Why would I want to look at my tank through a permanently mounted hydrometer? and 2 - Algae.
~Bruce
This is a good place to be - and the best place to gather information in an effort to solve aquaristic issues.
Speaking of which, and for the benefit of any future readers ... My "Instant Ocean" swing-arm hydrometer (I know - swing-arm hydrometers - but there are times that I just don't want to go through the rigamarole of pulling out the refractometer to get a ballpark on salinity, and this one had always been pretty accurate...) got so busted up that I decided to replace it. The most-local shop (Petco) was out of the Instant Ocean version, so I grabbed a "Fluval Sea" swing-arm off the peg.
Don't do what I did. Just ... don't.
The Fluval Sea swing-arm hydrometer has two readings. In fresh water, the needle rests on the bottom of the hydrometer. If there's any salt at all in the water, the needle will rise to the surface of the water within the unit. It's about as useful as throwing a rock at a chart. This model has a suction cup to attach it to the front glass of the aquarium, which puzzles me for two reasons. 1 - Why would I want to look at my tank through a permanently mounted hydrometer? and 2 - Algae.
~Bruce