What is the best filler for a tall glass vase with artificial flowers?

Local craft stores sell clear colored glass oblong pieces of glass. They are really pretty . If your vase is not opaque judt go with plain pummeled glass cheap sells at dollar store

Dollar stores as well have decorative stones, other fillers could be potpourri, shells,beach glass

depends on if you can see through it or not. I use sand...kitty litter...or just plain old artificial flower foam blocks from the dollar store. The glass stones are nice if you can see through the vase.

I like to use those glass beads as a filler. Colorful or clear both work depending on the look you want

I think white sand might look nice.

Dollar store glass beads. Comes in a variety of colors to match the flowers.

I thank you all for your suggestions

white sand and beads is great combination for oceanic design using a clear vase.