2009 chevy aveo lt 1.6 4 door. About 6 months ago had both upper/lower radiator hoses develop leaks mid-pipe at different times - fixed both, no leaks anymore. For about the past 2 months ever since my check engine light has came on (determined to be the thermostat) has been going through more than ordinary amount of coolant - every time I check its about halfway . Also have noticed snot-like build up inside the coolant rim as well as light brown colored fluid (coolant I used was florescent green) and possibly little oil blotches on fluid surface maybe? have seen some stuff on here about coolant & oil mixing? connection to a head gasket issue (no excessive smoke)? could i be using extra coolant due to thermostat that needs to be replaced? need help! eager to understand!