Hi Kate,
We are canoeists and have successfully prevented a lot of UV degradation of our plastic camping items by the application of a wonderful (but kind of pricey) liquid called "303".

We have used 303 for the past 10-12 years on the exterior of our Mad River 17' canoe, the dry bags and boxes, our roll-up tables, even our plastic patio chairs! I would highly recommend it to you.

I did a search for "UV Protectant" at www.rei.com - the URL below shows the entire result string.

Here is a link that might be useful: 303 Protectant at REI

Thanks Iris I will definitely look into it. Sounds like it would be just the thing except for how pricey perhaps. I am really wondering though if it is neccesary or not. . .

Anyone have experience with rain barrels degrading over time or not degrading as the case may be?? Heating up etc.??

Iris it does look good. Can you please answer a couple of questions.

How often do you have to apply it & how does it hold up when rained on or dumped in the river??

So I would really like some info on this. I know I am not supposed to cross post but can someone suggest another forum perhaps that would have folks with rainbarrel experience??

you can put a 55gal black plastic bag over the barrel, the trash bag need to be change every 5yrs or so. you can also buy a 10' x 10' UV treated tarp at wal-mart or harbor freight for 2$ a piece to cover you barrels, i use tarps to covered barrels and they seem to do well.