Frank,

A craft store would be your best bet for water crystals although not cheap. Maybe there are other resources folks can alert us to.

What about drip irrigation?

simply divine joe

Frank,
I found water crystals on ebay. 2lbs for 13.75. Free shipping. I thought this was better than anything I found in the stores around here. They sell in larger quanties also. The ebay seller is "jerseymarket" or the ebay store is "jersey-fleamarket". Let me know if you find any place cheaper.
Sydneypie