Question
My husband frequently buys me roses and they typically last a week or so. But, we recently installed a water filter and I filled the vase up with that water (and didn't add anything to it), and they were all dead the next morning. Why did the filtered water kill the roses?

Answer
Filtered water is often recommended for roses so I don't think it was the cause. I think the roses were not fresh when they were bought. All florist roses are kept in a cooler and although they may look fresh, if they have been in the cooler too long, then when they are taken out and placed in a warmer atmosphere, they will collapse. Here is a website that gives you a lot of information about cut roses. Maybe there will be a clue in it. Personally I think the roses need to be returned to the florist for a refund.
http://rosetypesonline.com/Keeping_Roses_Fresh.html