Hydrometers...

[MrBigglesworth]

Alright I don't trust the cheap seatest hydro the pet store recommended, it just seems kind of shotty.......someone said to test it in the actual ocean because its salinity is always in the required range....is that a good idea? Thanks.....

[Ledford]

 It should say on the package what the temp of you're water should be at for a correct reading as long as you follow that and don't drop it you should be ok.

[Delph]

(Edited by Delph at 9:58 am on June 3, 2002)

[fish04]

You can always get a salinity refractometer, which passes light through the water sample and gives you a super accurate reading...I saw one on EBay for $125.

[Kapelakin]

Thanks, I've been looking at that Marinometer, but haven't gotten an opinion on it.  Have you calibrated it against any other instruments?

 

The SeaTest floating-needle hydrometers are crap.  You can have two side-by-side and they'll read 0.005 differently on the same water sample, so who knows what your SG really is.

 

You can get a floating hydrometer for about $18 that's much better, though for nano you will need to find a tall thin vessel to put your water sample in.

 

Just don't rely on SeaTest, unless it's been calibrated to a more reliable instrument.

[gabe3eb]

Well, I personally don't see the need to spend $125 or even $50 for a digital salinity meter. Especially if you are running a nano. I would recommend that you go to the LFS with a water sample, take your "shotty plastic hydrometer" and tell them that you want to test your water and your hydrometer. Ask them for a couple of their plastic ones and test your water and their water. That way you have two seperate water samples, with different salinity. And you have several hydrometers, maybe they will even have one of the digital ones. This will tell you if your hydrometer is accurate or not. Especially before you spend all of that money. As to keeping your plastic one good, make sure you give it a good freshwater rinse, and it seems to me that someone told me they rinsed theirs out with vinegar. Don't take my word for it, it might have been something else and NOT vinegar. But the point is, I would strongly suggest that you be resourceful before elaborate. Good luck and if it works you can send that extra $125 to me. HTH

:freak2:gaber:freak2:

[fish04]

I wouldn't spend $125 on a refractometer either. Besides, salinity changes hour to hour based on temperature and evaporation. Especially in a nano! Honestly, the "shoddy" plastic ones are all I've ever used, I don't find great concern in the salinity of my tanks, the only time I ever use it is when I'm mixing salt for a water change. Most critters can take fluctuations from 1.017 to 1.025 (not fast swings). I've had readings up and down that range without any real problems. Obviously it's important to be as stable as you can but I wouldn't worry about callibration down to the thousandth or ten-thousandth decimal place.

The best way to keep your plastic hydrometer in good working oder is to clean it before and after use. The salts build up in the hydrometer and give false readings. Also, airbubbles in the sample tend to throw off the reading.

[Toyfreek]

yes,

You should rinse the swing arm type in vinegar after every use.

Ok heres what ya do buy a swing arm one, get it calibrated at the LFS, with a sharpie mark it. Buy like three of the $3.00 petmed glas 6" ones.  Mark them against your calibrated swing arm. now for twenty bucks you are always ready to calibrate your own.

The swing arm one will eventually go bad and it does it slowly so it creeps up on ya, one day you say my corals look droopy wonder why? and your SG has dropped like a stone only after trying everything else do you realize it. and then the swearing and promising to never trust one of these #$@%^&ing things again. God that was a really bad time.......anyhoo still usin a swing arm, I never remember to rinse it, but I do got three glass ones to check it with. And I do trust me.

HTH,

Toy