Hello; A few weeks ago I took part in a thread discussing the cost to operate equipment. I have a small meter and decided to test the cost of some of my equipment. I set the meter up and plugged into it an Aqua-Tech 30-60 HOB power filter. The measure started at 2:30 PM on November 8, 2012. I checked it today(12-1-2012) at 9:41 PM. If my count is correct that is 23 days. The power filter used 3.87 kWh in that time. It drew a steady 0.17 amps if I read the meter correctly. At 12 cents per kWh it calculated a cost of 46 cents. I have not run the numbers to check the meter, but if this is correct it cost two cents per day to operate this particular filter. I will reset the meter and test a different piece of equipment.