Condensation in headlight?

I got aftermarket headlights for my vehicle about a year ago. I noticed that the right headlight had condensation building up in it. Now the headlight looks like it has algae growing in it from the standing condensation. How can I get rid of that without replacing the whole unit?
Condensation in headlight?
A couple of squirts of chlorine bleach will take care of the algae, as for the condensation, remove the headlight housing and drill a small (4mm) vent hole in the rear of the housing, at the lowest point. Angled backwards 45 degrees, it will not pick up road spray, but will allow condensation to evaporate or drip out harmlessly.