A WARNING to all those using hydrometers

[theROYSKIE]

about a week ago i posted a thread titled "whats wrong with my bubble coral?" i honestly could not figure out what was wrong with the specimen. there r other corals in the tank including a big healthy branching hammer that were all doing fine and were visually healthy. and the population of calurpa in the tank is healthy and grow like weeds. all my water parameters were excellent, i perform an 8% water change weekly with R.O. water mixed with seachem salt mix and buffed( how shockingly bad tap PH is) and three times weekly the tank would be fed with a multitude of invert food ranging from DT's to the kent line of coral food. so as the bubble's health declined and as it began wasting away i went into emergency mode, 12% water changes every 48 hrs, treated the tank 4 red cyno bacteria( i had found something resembling red slime and decided to leave no stone unturned thinkin that the bacteria might have something to do with the coral's health). yesterday i calibrated my new refractometer and the results were astounding. before purchasing the refractometer i had used the "deepsix hydrometer". i had compared to over a dozen of buddies hydrometers and came to the conclusion that it was fairly accurate. i couldnt have been more wrong.i keep my water at- salinity-35ppt, and sg-1.0255 according to the deep six. the refractometer showed that my salinity was over 40ppt and the sg was over 1.032. my jaw friggin hit the floor. so today,after letting the treatment run its course i performed another water change(with a lower salinity to help balance out the levels) and put activated carbon into the sump to extract anything else that could be harming the tank occupants. the levels now r at approx 1.027 and approx 36.5 ppt. im taking care to not shock the inhabitants from the water they have grown acclimated to the correct levels. the levels should be at optimal in two days time.

already today since the lights have turned on the bubble coral looks like it is on its way 2 recovery.

it just blows me away that companies producing our reefing tools who r supposedly dedicated to quality equipment and development can sell a hydromter that doesnt [profanity]
SO A WARNING TO ANY REEFER USING A FLOATING NEEDLE HYDROMETER, PLEASE MAKE SURE U R GETTING AN ACCURATE READING. CROSS CHECK IT WITH OTHER TOOLS USED FOR READING SALINITY AD SG SUCH AS A REFRACTOMETER.

here is the bubble 3 weeks earlier



here is the bubble earlier this week(note the tissue line wasting away)



here is the bubble today

[bigian]

I think this is pretty well known. Ive seen 3 hydrometers, all the same brand, pulled from the packaging display different levels...

[plaereef]

Nice recovery, you could have lost many more.

[m2434]

Not all hydrometers are that bad. In my opinion, the deepsix hydrometer may be the worst one ever made. I tried one and it was WAY off according to my refractometer. Irronically, my 5yr old $2 genneric hydrometer was dead on.

[seapug]

I barely ever even use my hydrometer. If you mix your saltwater the same way and make a line on your sump and keep up with the topoffs there's really no reason why it should vary significantly over time. If anything, it will usually decline from salt removed by the protien skimmer.

Have you considered the possibility that it wasn't the Salinity, but rather generally poor water quality that was causing the problem? The multiple water changes and carbon might have significantly decreased pollutants from the excessive (IMO) liquid "coral foods" you have been using. Most of that stuff is bottled pollution, especially the Kent stuff. Just a thought....

Either way, glad to hear things are doing better.

[chrissreef]

thanks for the heads up!

[WangoTANGo]

Originally posted by m2434
. In my opinion, the deepsix hydrometer may be the worst one ever made. .

Uh oh.

Sorry for the hijack, but what are some accurate/cheaper refractometer models?

-Justin

[Nereaga]

You can find some ranging from $40-60. I got mine from Ebay for $36 w SH. I forget the name, any brand would be more accurate than a hydrometer.

Brad

[imyoraven]

thanks for the info