Mosquitos Breeding in my Grow-Boxes and Earthboxes

I've recently seen mosquito larvae in the water reservoir of my containers. The planters are situated in such a way that prohibits tipping them to empty the reservoir. I know that a film of oil over the water should kill them, but what type of oil should be used? I sure don't think I want to use a petroleum-based oil. Or is there an additive that can be added to the water that will kill the larvae without harming the plants (tomato and pepper)? Paul

This might be what you need:

http://www.biconet.com/biocontrol/bti.html

I think I need some myself because I use large containers filled with water to moderate the temperature in my greenhouse, and just recently noticed mosquitoes beginning to breed there.

LariAnn
Aroidia Research

Actually, LariAnn, this is exactly what I was looking for. After checking the company out in the Garden Watchdog, I placed an order for the Bti dunks. Thanks so much for the prompt response and helpful info. Paul