Krish I don't understand, the house you live in is'nt it insulated. If I had to live in a house at 81 deg. I would kill someone. We lived in apts inbetween boats a couple times and were in friends houses throughout our 10 yrs in Ft. Laud. and always the places were no warmer then 75 and some were kept around 72 mainly the apts we rented and i'm sure some of our friends homes too. I have been to the Bahamas alot and I know there is some old construction that is not all that insulated, plus the Bahamians just open the windows and let the carabean breeze blow through, with a ceiling fan running. If you have a room temp of 81 your in trouble. If I let my room temp get over 76 max. my tank temp well start climbing and if it gets 78 it really starts climbing. If you are not able to cool that house down to atleast 75 deg. you are wasting your time with fans alone. If you look at my canopy it is an open one on top with an aluminum channel bar running from end to end that slides fore and aft on runners inside each end and the pendents are mounted to the channel. My canopy is wide open on the top. It is also open on the ends. I didn't realize your room temp was that high, I thought you had it at 75, so you well have to bite the bullet and go the chiller route, no choice. Either that or go back to PC's and FOWLR and some softies even then you have to keep your house cooler then 81, atleast down around 78.
Steve you probably haven't read all the threads lately, there are so many new ones each day, but he had his tank temp down after removing the stand back, so that is not an issue anymore, it is MH's now.