Cyanide Fish in Stores.......

he was also a dedicated reefer who had started importing some of his own fish through wholesalers and was fed up with dying fish so he got some regents when he realized his photometer could do cyanide tests...
that was about 10 years ago, he tested my fish about 4 years ago

[saltcreep]

Here is a description of the method used with the ISE test. This is from a post on RDO by Dr. Peter Rubec who conducted this particular type of testing in the Philippines while with the IMA.

"Briefly, the tissue is mascerated in a blender with sodium hydroxide. The slurry is added to a distillaton flask and magnesium chloride and another chemical is added (two chemicals one to deal with inteference by nitrates and the other to act as a catalyst). Then the flask is heated to near boiling and hydrogen cyanide (HCN) gas is released.The HCN passes through a reflux condenser at a measured rate (about 1 ml per second). Then the gas is recaptured in an absorber tube containing concentrated sodium hydroxide solution at pH 12-13. Then, lead carbonate is added to precipitate sulfides (that can interfer with cyanide readings with the ISE electrode). The cyanide ion selective electrode is used with a known volume of sodium hydroxide to measure the cyanide ion concentration while linked to an ISE meter. Corrections are made to determine the concentration of cyanide ion based on the original weight of the tissue sample in order to determine the concentration in milligrams per killigram (ppm). The concentration in ppm determined with the ISE meter is done against a four point calibration with known cyanide ion concentrations. Calibrations are done daily. The apparatus can not be used in the field (but can be done regionally at field laboratories). A fume hood and space is needed for the apparatus. Tests should be done by chemists. Short of having a mobile trailer with the equipment, this is not a field test.

Peter Rubec"

Here is another post by Dr. Rubec which briefly explains the length of time cyanide will remain in a fish prior to it being expelled.

"Question-Please explain how long cyanide ion can be expected to remain in the fish being tested.
Answer-A common belief (misconception) is that cyanide ion is rapidly excreted and hence not detectable a short time after the fish were collected...Cyanide uptake and clearance studies have been conducted on freshwater fish, but not on marine fish. Cyanide ion is transformed to thiocyanate ion (mainly in the liver) by an enzyme called rhodanese. This process is slower than one might predict based on enzyme kinetics, since the conversion process is limited by the availability of sulfur in the fish.
Another factor which may influence this, and allow cyanide and/or thiocyanate to be retained in marine fish longer than with freshwater fish is the difference in osmoregulatory physiology. Marine fish excrete urine at a much lower rate than freshwater fish in order to retain fresh fluids in their blood. Hence, they can be expected to excrete cyanide at a much slower rate than freshwater fish.

A proposal to look at cyanide enzyme kinetics (uptake and release) was submitted (twice) to the Pet Industry Joint Advisory Council (PIJAC) by myself on behalf of IMA and the New England Aquarium in 1989 and 1990. PIJAC chose not to fund the proposed research. The IMA recently received a grant to look into these questions.

The quick answer to your question is that the IMA routinely was able to detect cyanide ion in marine fish tested by the 6 CDT laboratories in the Philippines at least 2 to 3 weeks after the fish were collected. "

It's my understanding that this is the most reliable method for CN detection and there are no reliable testing methods on this side of the water. There are studies ongoing in an attempt to establish a North American based testing method for cyanide detection. Not to be critical Kyle, but if the testing was just as easy as you have said, wouldn't there be testing being currently done for cyanide detection in fish? Or is there a conspiracy?

Cheers,

Kyle
CMA

[saltcreep]

Hey Kyle,

I just re-read some of this thread. You mention that the reagent used to test for CN was in the range of 0-0.5 ppm. What level did the results show?

[Beverly]

Originally Posted by AJ_77

That thread did freak me out a bit, but I'd like to see it archived - just in case I ever have to try it...

Can you point me to the force feeding thread? Did a site search and came up with 464 threads, none of which looked remotely connected to force feeding Thanks

[Aquattro]

Beverly, try this thread.

http://www.canreef.com/phpBB2/viewto...hlight=syringe

Originally Posted by saltcreep

It's my understanding that this is the most reliable method for CN detection and there are no reliable testing methods on this side of the water. There are studies ongoing in an attempt to establish a North American based testing method for cyanide detection. Not to be critical Kyle, but if the testing was just as easy as you have said, wouldn't there be testing being currently done for cyanide detection in fish? Or is there a conspiracy?

Cheers,

Kyle
CMA

Because of the freshwater only type of regent cyanide test that we had available to us, we let presumably contaminated fish flesh sit in a RO freshwater bath in a sealed container, I believe there was some blending of fish flesh as well, (I think my papers got put in the garbage when I moved from where I lived at the time of said test) when we tested the sample we produced a reading that confirmed trace cyanide(I dont remember the concentration)( also our test method was very primitave and unreliable but it did register a reading which led us to believe there must be cyanide present because when testing a regular RO water sample we produced no readings, I would call our method very inaccurate as to the concentration, but accurate to determine the presence of cyanide in our case) because I had 6 of these small adult angels shipped I had extras in the freezer to send back to the wholesaler who had them tested in a proper lab and confirmed our findings with a much more extensive test(all I know is that they said it cost them a few hundred dollars to get the tests done), they were mad and knew exactly what collector they came from(thats what they told me) they informed me that they would immediatly cease dealings with said collector and would inform others in the industry, I never had a problem after that...

[DOO-E]

I will agree i was appart of the "Bad practice" thread. I am sorry if i had offended anyone about what i said. I have 2 perfectly healthy Coast Mountain Clownfish , and a Coast mOuntain Banggai in my tank thriving. The clowns are a pair not mated yet. There is a Banggai from Coast mountain at a buddies tank thriving as well. I had seen fish in ill health in the store and had asked an employee what was wrong with it. This person told me it was cyanide so i assumed this was the problem. Once again i am sorry if i had offended any one.

[Beverly]

Originally Posted by reef_raf

Beverly, try this thread.

Thanks, Brad. Sounds like a sedative is necessary for the proceedures outlined by Kyle. For the fish, I mean

for the force feeding you dont need a sedative, just for surgery.... and you can give them a good scrubbing with out a sedative as well, only when need be of course....