Slider Help!

So I'm building a slider or at least planning on to. The slider is going to be about 20' but i need to figure out what i should use for floats and where a good place would be to find them. I want to be able to keep this fairly cheap if possible.

We just built a 32' slider and would like it longer. At 20, you'll be off before you can do a 180.

With that said, we used 30 (I think) gallon syrup (soft drink) containers. These can be found for around $5 each.

Were you able to get those online or was it somewhere local you got them. And now that you mention that i might have to reconsider the length.

I found the barrels locally. They are all over the place, you just have to look around a little.