The plastic sheeting you used I'm sure was a Low-Density Polyethylene (LDPE) same stuff they make Baggies out of and most likely made by the blown-film extrusion process... there are no processing aids that are used in blown-film, no additives are in the Polyethylene except for the colorant (black) which was likely "carbon black"... there would have been no coatings on the plastic and nothing to leach out of it. Rest assure whatever killed your koi, it was not related to the plastic itself... you must look else where to find the killer.
Last edited by monomer; 06-28-2013 at 01:38 PM.
Time is a great teacher, but unfortunately it kills all its pupils. - Louis Hector Berlioz
A computer once beat me at chess, but it was no match for me at kick boxing. - Emo Philips
Only one man in a thousand is a leader of men, the other 999 follow women. - Groucho Marx
There is a place you can touch a woman that will drive her crazy. Her heart. - Melanie Griffith
A man in love is incomplete until he has married. Then he's finished. - Zsa Zsa Gabor
You can tell you have created God in your own image when it turns out that he or she hates all the same people you do. - Anne Lamott