Is it best to keep the same water or change it for your cut flowers?

I change mine when the water looks bad, but this link says change it every day.

http://www.wikihow.com/Keep-Flowers-Fresh

it is always best to change the water every few days

Hello, Everything I am seeing says to change it every day.

ok thanks

Change every day, especially if in a clear vase. Extends the life of the cut flowers.

Not only should you change the water everyday, but you should also snip a little off the stems. There are many flowers that seal their "wounds". Snipping the ends helps them absorb the water. If your roses start looking droopy, take a lasagna pan put roses in and completely cover with water. Put in fridge overnight. They'll perk up and you can add them to your arrange. Should extend the life a little bit.

I like to change mine daily or at least every other day. I also keep stems clipped to allow for bruising of the stem in the vase and blocking water flow up the stem.