Five months ago I posted here a detailed cost of running my 125 gallon reef tank with the cost item by item. I used a Kill a watt unit. Electricity cost in Puerto Rico per killowatt is 19¢, higher than in the states.
These are the results of the estimated annual power cost for each equipment in my 125 gallon reef tank.
Power heads Koralia #1 - $9.98 X 2 = $19.96
Power head Koralia #2 - $18.30
Little Giant 4MDQ-SC 810 GPH pump - $144.00
Aquaclear 402 PH sump (backup UPS) - $14.97
Power head Maxijet behind the rock structure - $20.80 X 2 = $41.60
Sicce pump skimmer SWC Xtreme 200 - $39.94
Pump calcium reactor Ecoplus - $38.28
Metal halide 2 175w (8 hours) - $213.00
VHO 2 160w (10 hours) - $157.00
Fans for the Light fixture - $31.62 x 2 = $63.24
Light for mangroves - spiral fluorescent, 26w/100w 5K Satco (24h) - $39.94
Light chaeto algae - ecosmart 75w (24h) - $28.29
Chiller Current USA Tower 1/4hp - $44.90
Other miscellaneous equipments like the moonlights and Co2 tank solenoid were not measured.
The total annual cost to run my tank was $863.42, including other miscellaneous equipments is more or less $875.00. That is $72.92 monthly or $2.40 daily.
For more details here is the link
http://reefcentral.com/forums/showthread.php?t=1702895