Dogs can get heart worm from drinking mosquito infected water
No they can't:
Can Mosquito Larvae Cause Heartworm in Dogs?
The connection between dogs, mosquitoes and heartworm infection is well-established. Once confined to the southern portion of the U.S., heartworm infection in dogs has spread throughout the country. Having a good understanding of how your pup may contract this parasite goes a long way to keeping...
dogcare.dailypuppy.com
We checked this out with our vet when we first put the pond in as our dogs are OBSESSED with drinking pond water. They ask to be let out just to get a drink from the pond, passing right by the clear, clean, cool water in their dish on their way out the door!