Where to get southdown sand?

[Rikko]

You're not going to find it outside of the Northeastern USA.
It is possible to transfer a quantity of it here, but I think when someone checked it was an ungodly number of skids.
You could also look into Bomix play sand. It's calcite, rather than aragonite, but many reefers in Eastern Canada are using it happily. Most of those guys are on www.aquariumpros.ca .

Yes, Caribsea is certainly milking us and it doesn't look like there's much we can do.

I did receive an email from a local company (I was bugging Target Minerals about Calcium Carbonate sands and he forwarded me along to his friend) called Chemical Lime who are local (Langley I think) and have large amounts of Calcium Carbonate sand available. Again, I think it's calcite rather than aragonite (I don't remember if I followed up with him). Here's what he sent me:

Re: small quantity of calcium carbonate, we at Chemical Lime have various
mesh sizes of limestone, calculated CaC03 guaranteed 97.00 percent, the
one mesh size you may be interested in is our 14-100 mesh ( sand like
particles). attached is the typical screen analysis for the 14-100. We
supply our limestone in 20kg bags 50 per pallet @ $84.50 per metric tonne (
$1.69 per bag ) and 1000 kg bulk bags ( super sacks) @ $53.00 per metric
tonne plus $18.00 per bag and $10.00 per pallet. I you wish further
information please contact me. Thank you.(See attached file:
TEXST14-100.DOC)

I might test it out on a nano and see what happens with it. Can't beat $53 a TONNE.