testing salinity

[JohnD]

What do you folks use to test the salinity of your water? Are you happy with the tester?

 

[louey louey]

Deep six by coralife. Works great and you don't even have to stick your fingers in the water!

 

[MediaOne]

I second that notion. Originally I purchased the box type by Aquarium Systems but that thing was a pain. One day while rinsing it out the slider that holds the arm in place came out. and broke on the floor. Sometimes the unit also stuck on say 1.022.. and a slam brought it way up to the 1.024 it is supposed to be at..

never trusted it.. it would give me 3 different readings if I did three in a row!

So I went with the deep six. Accurate, easy, DRY HANDS! and fun! haha

Good Luck

 

[reefmack]

i'd love to get rid of my cheap-o salinity tester too - but don't want to spend an arm and a leg... where to you get a deep six from corallife? i can't find it at Marine Depot or Premium Aquatics (my e-shops

)

is it comparable to a pinpoint salinity monitor (w/ probe) damn - those are 114 bucks!

 

[AlexS!]

i've got a pinpoint, and works like a charm. If you are really serious/ or have a problem with salinity (me

) than go with a pinpoint, or even better a refractometer

 

[jdeets]

I have a Deep Six that works great. I don't use it now because now I use a refractometer. The Deep Six is so good that sometimes I still use it to confirm that the refractometer is calibrated!

 

[JohnD]

I confess, I have an old seatest hydrometer. It has seen better days and I am looking to upgrade. I was looking at the Tropic Marin hydrometer for $19.95 and the eSHa Marinomat hydrometer for $34.95. Both are at Premium Aquatics.

reefmack,
www.thatpetplace.com has Coralife Deep Six hydrometers for $6.99. I can't believe the price and you folks swear by them. Wow!

Anybody else have any other comments?

JohnD

[ July 07, 2001: Message edited by: JohnD ]

 

[fishrfun2001]

Deep six gets my vote too.

Remember, stability is the best measure. The ocean doesn't change drasticly and neither should our tanks.

I know people who have a 40 gallon tank and let the water evaporate for almost a week and then all at once just pour in 2 or 3 gallons of freshwater right into the tank. Whew !!! I would never do that to my animals. Too drastic of a change.

 

[acecool]

I bought a eSHa Marinomat hydrometer thinking my Deep Six is to old to be my main meter and that was a mistake... The eSHa Marinomat hydrometer is a piece a s$%#t and because was giving me wrong readings all along and I did not trust my old Deep Six andf I should have. I confirmed the DeepSix is the correct reading after I got the refractometer so I returned the eSHa Marinomat hydrometer altough I never got a received a credit back but, that's another story.

 

[Terry B]

Most plastic swing arm type hydrometers are notorious for being inaccurate. I am curious how low the Deep Six unit will read. I have been careful to use large glass hydrometers that are calibrated for temps in the high 70s or a refractometer. I would really like to know how dependable the Deep Six is for reading a specific gravity of 1.009 when treating fish with hyposalinity.
Terry B

 

[SPC]

I use both a SeaTest swing arm type and a refractometer. I check the SeaTest periodically against my refractometer to make sure it is still accurate, so far so good.
Steve

 

[Tanu]

Acecool, you're right about the eSHa marinomat! A friend of mine bought one, after checking with a calibrated AB aerometer at the lfs it stated that his salinity was 1.012 instead of the 1.023 the eSHa read!

Don't know if they're available in the US, but in Holland the JBL aerometers are the best deal. In a lfs we compared 10 JBL with the total stock Aquarium Systems'boxes, a calibrated AB, and a digital Aqua Medic. We threw away about half of the boxes, ALL of the JBL's were fine, so was the Aqua Medic. This lfs only carries high quality products, so no cheap (*&$^#^&#.. ;-)

I've followed a traineeship there, and now I'm even more convinced about their quality and skills.. Wow!

Tanu
www.tanu.nl

 

[jdeets]

Someone correct me if I'm wrong, but I believe the Deep Six automatically adjusts for temperature variations. Just dip-n-read. It's got a little "button" on the swing arm which, I believe, changes density based on the temperature, resulting in an true reading at any temperature with no conversion table necessary.

 

[Mike02]

I agree with Terry B. I think the swing arms are inaccurate because the slightest tiny bubble on the swing arm will result in a false reading. its impossible to get those bubbles off. i bought one and regret it but it was only like $8. im sticking to my floating hydromter which i bought 26 years ago when i was 12. the only problem with that is its calibrated for 68degrees so you have to adjust. the more modern ones are calibrated for 77degrees. The floating ones are accurate to within .001 which is good enuff. refracometers might be more accurate but not worth the $$. its like paying an extra $70 for a mecury thermometer thats says 91degrees instead of 90degrees for your alchohol based one. depending on your application, 1 degree doesnt matter much.

 

[JohnD]

I picked up the Deep Six and the construction is better than the SeaTest hydrometer. The plastic is heavier. I am happy with the purcahse.

jdeets - I did not see buttons to adjust for temperature.

Terry & Mike - I have always tapped the side of the hydrometer to remove the bubbles. I don't think I ever had a problem, but I could be wrong. I am considering the purchase of the Tropic Marin hydrometer also.

 

[Len]

I'm compelled to repost the differences between salinity and specific gravity (a pet peeve of mine):

It's an issue of semantics, but we're measuring specific gravity with hydrometers, not salinity. Though there is a positive correlation, they aren't the same: Specific Gravity (s.g.) is the ratio of densities of ions in solution compared to pure H2O (reference s.g. of 1.000 at 4 Celcius). These ions are constititued of different matters: salts, minerals and/or elements. S.g. must be corrected for temp and pressure. Salinity is the measure of total solute concentration in 1kg of water (essentially, remove all the water and weigh what you've got left). Salinity figures need not be corrected for temp or pressure.
Most people mistakenly use the terms salinity and s.g. interchangably.

With that said, I use a refractometer to measure my s.g. It's so much more accurate and consistent then all my previous hydrometers. Bobbing style hydrometers are more accurate then swing-arm styles, but need to be compensated for temp.