I want to replace the gravel in my fish tank with "flattened marbles", I believe you call them glass gems. Problem is I will need about 50 pounds of these, so bulk pricing is essential. I've found a few places in the US (McGills, Alamo Toy, US Marbles) but shipping costs are fairly high.
So I went looking locally and found bags of decent looking gems at the Dollar store. Problem is all the decent looking ones were iridized. These are all made in China, so I'm concerned that safety is not their main concern. I don't want these things leaching Copper, Lead or some other toxic chemical into the water. How is glass iridized?
I think Walmart carries these things too, but probably still made in China. Although my might have a greater selection of the non iridized variety. Cobalt Blue is preferred.
TIA