Hey Skip:Originally Posted by skiptomylu
I've never built any that I didn't sink within a day or two but I don't know why it would be a problem. They will dry out quite a bit in a week, which I guess would make them more buoyant but I don't think that would be a problem as long as you have plenty of weight.
We've cut some and put the butt ends in the lake and they stayed fairly green for several days. If you leave the Quickcrete a couple inches below the top of the bucket you could keep some water in the top of the buckets, which would keep the concrete wet (actually makes it cure stronger oddly enough) and I think that might help keep the bamboo from drying out too much.
Try it and let us know how it works!