can a refractometer break?

[OhTheHumanity]

I had a CBS die on me and I returned it to the lfs. At home my water tested at 1.0225 at the lfs it tested at over 1.030. The lfs used one of the needle style hydrometers. In my QT my hydrometer reads 1.030 and my refractometer reads 1.021. Which is right?

Can the refractometer be that far out of whack? I calibrated with the water from my fridge that runs through a filter. Makes me wonder if my salinity is too high and thats why the CBS died.

Any ideas on which to trust?

 

[Dewey]

I would use distilled water to calibrate.

Dewey

 

[reefrunner69]

I also wouldn't use cold water to calibrate it. Calibrate with RO/DI water or distilled, and see if it is calibrated correctly. FWIW, even though it was basically cold tap water, I would still trust the refractometer over the swing arm hydrometers.

1.0225 seems low and I would expect a shrimp to have problems at that low an SG.

 

[OhTheHumanity]

The refractometer I'm using is a step up from the rhs 10atc. It is an rhb 200 made by the same company, Westover.

Although it doesn't have SG it does have urine gravity which is the same thing if calibrated at 0.

Could I be wrong?

 

[OhTheHumanity]

BTW I was using the hydrometer when I bought the CBS. Which explains why I thought the SG was right.

I also dropped the refractometer in the tank, it wasn't in long. Could this affect it?

 

[Dewey]

oooooooooo it might

 

[reefrunner69]

Yes, it could very well mess up the way the prism works, I don't know if they are sealed well enough to prevent water getting on the other side of the prism or messing with the optics. I also do not know if urine gravity and specific gravity are the same. I would suspect that the RHB 200 is not necessarily a salinity refractometer but one used for medical purposes. Does it have ATC?

 

[reefrunner69]

Urine Specific Gravity


Alternate Names : Urine Density, Urine S.G.

Definition
This test measures the specific gravity of the urine, which is a reflection of the concentration of particles in the urine (see also urine concentration test).

Looks like it is a simple specific gravity tester for urine. I personally would use a salinty refractometer as salinity is what you want to know, the SG is effected by other minerals in the water.

 

[OhTheHumanity]

Okay DO NOT use a urine SG refractometer to check salt water Sg!!!! lol

I checked my hydrometer in a CLEAN flower vase filled with distilled water and it read 1.000. UH OH all the water I've made the last 2 weeks is at 1.031.

My tank water is also 1.030. How do I get it down quickly, but safely?

 

[reefrunner69]

pull out a gallon and replace with a gallon of FW. Test and see where your at, do not change more than .001 per day.