I had Mosquitoes in the house when I was culturing blackworms + larvae with the blackworms (cultured in freshwater). You've got a few months of hell until the mosquitoes can die off.
The only way to deal with them is let them live out their cycle (its only a month or two) and close up the house and turn on the air conditioner.
Don't leave any fruit out or flowering plants - Females / Males require fruit (nectar) for their normal day to day.
http://www.mosquitoreviews.com/mosquitoes-eat.html Once the females are ready to reproduce - that's when they turn into blood suckers.
If you got the larvae - you probably have two more lifecycles to go before they are gone.
another weird thing with the mosquitoes - I never had them in my freshwater reservoirs (90 gallons - around 4.5 foot high) - only in the blackworm culture (well fed well aerated). I know they could have gotten in there and laid eggs / produced larvae as it's vented - but I never saw them in there.
As for your original question - it's not bad for your tank but will annoy the heck out of you having mosquitoes buzzing around the house especially at night. You'll never get rid of them by just waiting them out and hoping they get pumped into the tank. You'll need to starve out the life cycles you have going now (eggs + larvae + pupae + adults) and not let any new ones in.