I understand 67-68 is IDEAL. But I also know lower water temps = more O2. But, am I to low? Any thoughts/comments from members with experience in this matter? Not just what you hear or read, but real life trial... Just asking because I moved and in old house, res temp was right on the money and I do not want to have to spring for a heater unless its needed...plants are new in table, 3 days and look a bit depressed. Trying to figure out why....and if my H2O temp is freakin them out..lol. Thanks to all. Merry Christmas!