Marineland Hydrometer

[ZBT3091]

My marineland hydrometer has been getting stuck on the bottom and wont lift or budge at all when i add water. If i put hot water in it seems to get unstuck. Im thinking the salt may be crystalizing and causing it to get stuck. Im just afraid that even when it gets unstuck it throws the levels off so that the hydrometer is not working. Should i just get a bobbing thermometer/hydrometer?

 

[Pedro Nuno Ferreira]

Hi
You should get a refractometer for accurate and reliable measurement as Hydrometers are not as precise and reliable. I use a Milwaukee refractometer with automatic temperature compensation like this one

Refractometer
Having and using a refractometer is a no-brainer. For years, aquarists have been offered and then lamented the miserably inaccurate products available at low cost to measure what is arguably the most basic and important parameter in reef aquaria - salinity. While many organisms can manage relatively short periods of salinity change, prolonged exposure to sub-optimal salinity is literally a killer. I cannot count the number of problems that have befallen others and myself through inadvertent, unrecognized, accidental, or lackadaisical carelessness in salinity measurements.
I think many people are probably aware of the poor accuracy, especially over time, of plastic swing arm-type hydrometers. Many floating glass hydrometers are either cheap and inaccurate, or are expensive and accurate but calibrated at temperatures far from those where reef tanks are kept (requiring inconvenient and possibly inaccurate scaling techniques to arrive at true salinity). Furthermore, glass hydrometers are not convenient to use in tanks where they are not easily stabilized and read because of water currents, rocks, and tank walls. Conductivity probes are expensive, require calibration, and give readings that vary from accurate to inaccurate depending on any number of factors (see Holmes-Farley 2000, 2002). Furthermore, conductivity does not measure salinity in parts per thousand, or as a reading of specific gravity, which are scales commonly used by aquarists.

However, there is now a ready availability from aquarium sources of devices called refractometers that are generally quite accurate, easily calibrated, extremely quick and easy to use, and inexpensive, to boot. I say this loosely, since I regularly use a refractometer that is not inexpensive at $280.00, but I also have one that reads identically to it and costs $69.00. Most of the refractometers available in the aquarium trade today are also temperature compensated so that no special calibration is needed for temperatures of reef aquaria. They are a lifetime investment, require little care or maintenance, and are so easy to use that accurate salinity measurements can be taken daily in a matter of a few seconds. I cannot fathom any reason why any aquarist should not have one of these devices in their aquarium repertoire.

Cheers
Pedro Nuno ;-)

 

[Klewis]

I've had the same problem. If you rinse it with fresh water every once and a while it should be fine. Don't use too hot of water or that round insert on the lever will fall out then the hydrometer will be useless. Good luck, and the holidays are coming. Put a refracto meter at the top of your list.

 

[MikeyZO]

Hey Z. Definately look into using a refractometer like Pedro said. Here's the one I got. Not too expensive and works well. Make sure you also get the Pinpoint calibration fluid also, as calibrating it with distilled water will sometimes give you lower readings.

http://www.fishtanksdirect.com/index.asp?PageAction=VIEWPROD&ProdID=9

http://www.petstore.com/ps_ViewItem-idProduct-AM1437.html