For years I have used the 'solar fish', but many of these have been discontinued. This year I bought the "heatsavr" liquid. It is 90% ethanol. According to the manufacturer, a few years back they converted from isopropyl alcohol to ethanol, a "bio-based liquid made from corn". http://cloud2.snappages.com/86820d31...nouncement.pdf
I did read one review where the guy complained that it made his water cloudy, but otherwise most of the reviews are good.
Thanks for any thoughts.
UPDATE - I just found a thread that deals with liquid solar covers by searching through the forums...which leads me to another question - why can't I find the thread that I came across in a search by looking through the 4 pages of the actual forum (the section that deals with 'everything else". That doesn't make sense. It should be there, unless there are 'archived' threads that don't show up.