Unfortunately, this product cannot hold water as the caps do not deal properly (had an issue with 2 of 4 of the base weights). Ideally, I'd prefer to use water over sand. If you use sand, no problem. I tightened by hand and didn't want to bring out pliers to tighten further, risking damage. Although, in my opinion, plier shouldn't be necessary to get a proper seal. Definitely disappointed in another item purchased from Wayfair.