I think this all depends on many factors.

I've run a 1000w MH over my fish tank for years, PLUS I run a 500w MV bulb over my iguanas(UV). I live in a 14x80 foot moble home and my Excel energy bill averages $75 in the summer and $280 in the winter. I've never had any issues.

SO, I'd guess it has more to do with suddan changes to your usage then how much you use. I know my aunt had a gas leak in her yard a few years back. It was outside so she didn't smell it. When the bill came it was huge! SO huge they sent out a technician to ask about it. They ended up fixing the leak and just charged her for the previous months average.

Point is, if you use WAY more then you ever have and have no explaination why, then you could have an issue.

I'd suggest calling the power company to ask them how much extra it would cost if you were to buy a MH lighted REEF fish tank running a 1000w MH. They will generate a number for you. this "cost quote" will not only tell you what to expect on your bill, but will also give them a recorded call asking about the usage for a fish tank .

I never did this, because it WAS on a fish tank. Now that MMJ is legal here(Medical use) I won't tell them anything this time either. However doing this might take any questions they may have in the future and toss them, thinking you bought a fish tank. :thumbsup:

Good luck