Bert - 8-3-2015 at 14:34
Found this in the local Fleet farm...
$26.00 for 50 lb. Probably cheaper in bulk at a grain elevator, but bag is easy to handle, and cheap enough for some home chemistry uses.
http://www.fleetfarm.com/detail/sprout-18-5-dicalcium-phosph...
[Edited on 9-3-2015 by Bert]