Great meeting today Randy! You answered so many good questions I wish I had taken some notes. Definitely took some good mental ones though. You are definitely the best chemistry book we could ever hope to have access to. thanks again.
I really enjoyed it and I'm glad you found it useful. maybe we can do it again next year or the one after that.
Since you weren't there, Cindy, I didn't go into your copper dust question, but I did a calculation and I do think it is worth worrying about it for any pipes near open tank water. Only 26 mg of copper would double the amount of copper in your 700 g tank system, assuming it starts where mine does around 10 ppb. I'm not sure how high you'd need to get before having problems, but I wouldn't want my copper to double.
Copper is also pretty dense, although the copper oxide/hydroxide dust is probably fluffed up. But 26 mg of copper as copper hydroxide is not much, about 1/100th of an mL (not accounting for fluffiness).