Old wives tales- or are they?!

[jmaneyapanda]

We all know that this hobby is littered with misinformation, old wives tales, as well as perpetuated rumors and myths based on heresay and speculation. I got to thinking recently, which of these are actually true and have been observed, and which are not?

I am a VERY skeptical aquarist, and tend to not believe things (especially the outlandish) without absolute proof, or repeated confirmed documentation (with peer review). Simple forum postings of second hand accounts dont cut it for me.

For example, I laugh when I hear of people calling mantis shrimp "thumb splitters" and warn others to be careful, otherwise, your only have 9 fingers instead of ten. What!?? Who has ever lost a finger, or even been mildly injured by a mantis shrimp? If so, show me.

So....that gets me to my request. If there is a reef myth or rumor, or misinterpretation that drives you nuts, what is it? And, conversely, what "rumor" do you know to be true, and SHOW ME THE MONEY!!

[rbursek]

Calibrateing a rectormeter for salt water use with RODI to zerro and expect it to be accurate for salt water.

[jmaneyapanda]

Originally posted by rbursek
Calibrateing a rectormeter for salt water use with RODI to zerro and expect it to be accurate for salt water.

Whats a "rectormeter" and what is it used for?!

[hyperfocal]

It's for measuring coral COLONies

[rbursek]

Sorry, misspell, refactormeter, it is used for testing for specific gravity of liquids, but when calibrated with RODI water it does read salt water accurately, they must be calibrate with a solution that is made for calibrateing them for salt water which is Pinpoint 53s.

[jmaneyapanda]

Originally posted by hyperfocal
It's for measuring coral COLONies

[BigJay]

I dunno, I used to think that bubble anenomies suddenly deciding to "take a stroll" around the tank and sting the crap out of every coral in it's path was a myth.

[snorvich]

Well, sorry the mantis shrimp information is actual. The stories come from fishermen not aquarists. But they will not dedigitize you just give you a rather painful thwack.

[MThompson]

You should calibrate a re'fra'ctometer with a known salt solution....I don't know what to calibrate a rectometer with (I probably don't want to know).

I've always been skeptical of the magical sugar or vodka -bacteria
thing...haven't seen any plausible science behind it.



p.s. - i am catching a waft of th.o.t.m in the air!

[snorvich]

Btw, I think he is saying refractometer. The other device is best left for nonaquarium usage.

[jmaneyapanda]

Originally posted by rbursek
Sorry, misspell, refactormeter, it is used for testing for specific gravity of liquids, but when calibrated with RODI water it does read salt water accurately, they must be calibrate with a solution that is made for calibrateing them for salt water which is Pinpoint 53s.

Yeah, I know. I was only joking around. However, I disagree with your comment to a certain degree. Your statemnet is very true depending on the quality of manufacturer. If the sacle and calibartion at factory was done well, the refractometer should be usably accuarte at the range of 35 ppm. However, if the refractometer was made in a sweat shop by underpaid slaves, then it will likely have a very poor scales, and will likely be way off.

However (depending on your definition of calibrate), you would really only need to confirm the validity of your refractometer once with the calibration fluid you mentioned. If it is supposed to be 35 ppm, and it reads 39 ppm, you know that in the usable range, it is 4 ppm high. So you can calibrate it with RODI, and just subtract 4 ppm every time. A hassle, but not an impossibility.

[jmaneyapanda]

Originally posted by snorvich
Well, sorry the mantis shrimp information is actual. The stories come from fishermen not aquarists. But they will not dedigitize you just give you a rather painful thwack.

But this is exactly my point. A seocnd hand "I heard from a fisherman" reference. How does "a painful thwack" get translated into "it will split your finger wide open"? Search mantis shrimps stories here on RC, and see how many people claim that a 1" mantis shrimp will disfigure someone for life. That is the "myth" taht drives me crazy, or needs to be verified/confirmed (legitimately).

[MThompson]

Sounds like someone is volunteering for a little study?

[rbursek]

My friend was up gradeing to a 180 and when we where moveing LS either his CBS or Purple lobster got him and broke the skin open, I saw it happen, just a little cut.

[rbursek]

Saw a thread on reef santuary on calibrateing a refractormeter with water I chimed in and 2 pages later, finial Boomer chimed in with Randy's article to explain it in detail. If using RODI it will be reading 33.5 instead of 35ppt when checked with a calibrateing solution.

[jmaneyapanda]

Originally posted by rbursek
Saw a thread on reef santuary on calibrateing a refractormeter with water I chimed in and 2 pages later, finial Boomer chimed in with Randy's article to explain it in detail. If using RODI it will be reading 33.5 instead of 35ppt when checked with a calibrateing solution.

Hmmm....Please post a link. I would very interetsed in reading that.

[useskaforevil]

i don't think anybody thinks a 1" mantis shrimp will take off your finger. but some species get to be over a foot and a half. sorry no firsthand proof because i'm smart enough to keep my hand away from creatures that skewer fish the width of my thumb faster than my eyes can see.

[xtm]

"stray voltage causes HLLE"

"DSB's are ticking time bombs"

"too small of a tank for tangs causes ich"

"good PE = good health"

"starfishes are detrivores"

"glass tanks are unscratchable"

[rbursek]

I have not learned the skills for posting links, it was at reefsanctuary forum group buys, refractometers, the last 2 pages. Also if you want Randy's article on it go to the chem forum and look for a thread from me on Looking for a article from Randy, I posted ot today, the link to his article is there.

[rbursek]

RC chem forum.

[jmaneyapanda]

I checked out that article. From I took from it, it doesnt say that using RODI will give you an incorrect reading, it says that using RODI on an incorrect unit will give you a incorrect reading. That was my original point. If the scale is out of whack, then it will read incorrectly. If the refractometer is high quality, in can easily read correct with the RODI calibration. He even states that. Nonetheless, I would agree is is better, and eliminates all doubt to calibrate with fluid, rather than RODI, but I dont think that the claim that RODI=wrong can be made.

[Michael]

trust me i know rburesk knows his stuff if he says its 33.5 and not 35 then it is,it is well known in the hobby that you do not calibrate a refractometer with ro-di, you use a solution which is easily available, i have read the thread as well and i understand your point but i totally agree with rburesk

[Michael]

Originally posted by jmaneyapanda
Yeah, I know. I was only joking around. However, I disagree with your comment to a certain degree. Your statemnet is very true depending on the quality of manufacturer. If the sacle and calibartion at factory was done well, the refractometer should be usably accuarte at the range of 35 ppm. However, if the refractometer was made in a sweat shop by underpaid slaves, then it will likely have a very poor scales, and will likely be way off.

However (depending on your definition of calibrate), you would really only need to confirm the validity of your refractometer once with the calibration fluid you mentioned. If it is supposed to be 35 ppm, and it reads 39 ppm, you know that in the usable range, it is 4 ppm high. So you can calibrate it with RODI, and just subtract 4 ppm every time. A hassle, but not an impossibility.

actually after reading this again i can understand your point

[rbursek]

Go back to it and read under diagrams 19-22, If adjusted to read accurately between the range of 1.020-1.030 it will not read Rodi at 1.000, so to turn that around if you calibrate with RODI to read1.000 it will not read salt water accurately it the 1.020-1.030.
The solution is Pinpoint 35s, When I calibrate mine it was off, then Randy told me for giggles to check what it read with RODI, it read 1.5 not 0 so if calibrated to 0 with RODI when you are checking saltwater you will have 33.5ppt andthe refractometer will read 35ppt/1.026.

[jmaneyapanda]

Originally posted by rbursek
Go back to it and read under diagrams 19-22, If adjusted to read accurately between the range of 1.020-1.030 it will not read Rodi at 1.000, so to turn that around if you calibrate with RODI to read1.000 it will not read salt water accurately it the 1.020-1.030.
The solution is Pinpoint 35s, When I calibrate mine it was off, then Randy told me for giggles to check what it read with RODI, it read 1.5 not 0 so if calibrated to 0 with RODI when you are checking saltwater you will have 33.5ppt andthe refractometer will read 35ppt/1.026.

Yes, my point is that the references diagrams were in the context of a refractometer with an incorrectly established slope. So, if the refractometer itself was poorly designed/made/whatever, this would eb a problem. However, if it was a quality unit, this will not be a problem, because the slope will be accurate.