Pearl Sutton wrote:Today I was messing with an inflatable exercise ball, the kind you can sit on, and thought about it... If it was cut in half carefully, that's an impressively thick flexible plastic that would work like a pair of pond liners for a neat fountain! ... :D
Here to play devil's advocate:
1. What shape is the ball when there's *no* air in it? How big is it? It is not as stretchy as a balloon, but is it actually big enough with no tension on it?
2. There are some exercise ball-like toys that are probably designed to have reasonable UV stability, but how true is that of exercise balls? It isn't just about how long it will last - will it leak nasty stuff into the water as it's degrading? I suspect if you build a fountain, the birds will come! So you may find it will be good for holding water, but need something to line the liner to keep the sun off?
3. The former owners of our property had built a much larger than ball sized double pond with waterfall.
The issues were:
A) no reservoir to accommodate the difference between "just sitting" and "water flowing" states. You may not want to use electricity to run this all night, so you might need to be able to scoop some water out as you're turning it off.
B) A *lot* of water evaporated during a sunny day with all that water running, so the lower pond got too low on water and damaged the pump.
C) they didn't include any sort of a filter, so a lot of crap built up which was difficult to remove.
So I would consider easy ways to clean it and maintain it from the get-go. That said, the cute water features that have water coming out of the spout of a watering can are darn cute and would likely be in the ball park of the size you're dealing with. If you end up deciding that the balls just won't work, getting a food grade plastic barrel might not be too hard in your area and I've seen lots of those turned into pocket ponds. New barrels seem to have less plastic than old ones and don't stay round, but I've asked for old bicycle rims at local bike shops and used those to reinforce the cut edge to keep it acceptably round. Good luck and post pictures please.