I had been using the 3 year typical life "blue" bubble cover but most recently bought a longer life (5-7 year) clear cover and it is holding up fairly well after 2 years in northern California. Is the one any better than the other for loss of chlorine? Has anyone ever measured this with instruments? I am more concerned about water loss (evaporation) and Chlorine loss during the Summer than heating the pool here in draught country. The pool cover is a real saver on evaporation of water. I am losing almost no water with the cover on vs. 1/8-1/4" per day during the Summer with the cover off.