Even more suggestions! Mold problems? Buy this!

http://www.amazon.com/Natural-Industries-LGAV02-Actinovate-Fungicide/dp/B0026KSLG2

I've never had a moldy tray since I started using this, I don't even sanitize seeds anymore. I just water everything in with a couple of gallons of water mixed with about 1tsp of the stuff, and it works great. A small bag will last you forever. Best of all; It's a totally organic fungicide!