i recently purchased a cardiff and am having problems with it running hot. with no lights it is running 82-83 degrees. we keep our home at 72. i have contacted the store and manufacturer and both assure me they havent seen this before. i guess i am having trouble believing this isnt an issue with this tank, since it has been like this from day 1. i would feel better if others that own these confirm that they dont have this issue. they are sending me another pump to try, but mine isnt warm to touch or anything. i am afraid this is a design flaw, and that i have spent a lot of money on something that isnt going to work for me.:frustrat: