Hard lesson learned

[cherylann]

For some reason I thought that my specific gravity was off, so I took some water to my LFS with his hydrometer I learned to my horror that my specific gravity was 1.032 instead of 1.025 with the swing arm that I always use and keep clean, look for bubbles and rinse after every use was a very inaccurate, never had this problem before. I did not lose any inhabitants yet my snails were acting weird. So if you have a swing arm, get rid of it and pay the money for a actual hydrometer, for the money and time I spend on my tanks the hydrometer is priceless. Learn something new every day and I knew that I should invest in a hydrometer yet, there was alway another fish, clam or coral that I spent my money on. Did a 12 gal H2o change on the tank prior to testing at the LFS so I know that the swing arm was trash.

 

[meowzer]

Maybe you should get a refractometer......hydrometers are very inaccurate

 

[cherylann]

Yes it's a refractometer just so suprised at the near mishap, that I incorrectly identified it. Plus it's not cheap, but much cheaper than the money I have invested in my tanks. Thanks for your concern.

 

[meowzer]

You got that bad reading with a refractometer????

 

[katsafados]

Hydrometer = swing arm (shows how boyant the salt is making te water, since salt makes things float, less accurate due to air bubbles, not cleanning the arm properly and other things that can go wrong)
Refractometer = the insturment that looks like a telescope. (more accurate, shows how the water is bending light, which gives you your results) I use these things (on a much larger scale in my labs to identify unknown liquids based on their refractive index(how each liquid bends light rays when light is passed through it.)
I think you got the two mixed up lol.

 

[cherylann]

No I paid the price for a refractometer. No more swing arms for me. My tank the Jbj is over a year old and the Aqua pod is 3 months, the swing arm must have just started to read inaccurate otherwise I would have fatalities by now and seen the adverse side effects. I noticed when I would added 1 gal of ro/di and 1/2 cup of Instant Ocean and the reading would be 1.022 consistantly lately so I decided to check with my LFS.

 

[curry]

Any pictures of it?

 

[matth2181]

the swing arms are also calibrated by temperature, usually at 77 F. swing arms show SG which is not EXACTLY the same thing as salinity, SG is temperature and salt dependent. if your temp is more than that youll get a higher reading, if it below that youll get a lower reading. but ur right a refractoemeter is much safer and much accurate, no doubt, i use a swimg arm personally, but every once in a while i bring in some water to my lab and use their refractometer.

 

[snakeblitz33]

Definately use a refractometer - but you still have to be careful with those as well and use a calibrating solution (or absolutely pure water) to calibrate it. Then, keep in mind that salinity changes as temperature changes.