I hate lids too! I'd move fish before using a hood. I don't care about evaporation loss either... lol!
That will make adding 2 more bulbs a lot easier for you. When I added more light I got a touch of hair algae in one spot and a little thread algae in another area. I had to make some photoperiod adjustments, lowered my micro's a touch as that seems to be what is giving the thread algae what it needs with the extra light, and that's about it. I did do spot treatments in those area's to get it under control faster. When you add 2 more bulbs try running them 2 hours the first couple week, then add an hour for a couple more, and continue until you build up to 6 hours. That way your not flooding the tank with double the light all at once.
That will make adding 2 more bulbs a lot easier for you. When I added more light I got a touch of hair algae in one spot and a little thread algae in another area. I had to make some photoperiod adjustments, lowered my micro's a touch as that seems to be what is giving the thread algae what it needs with the extra light, and that's about it. I did do spot treatments in those area's to get it under control faster. When you add 2 more bulbs try running them 2 hours the first couple week, then add an hour for a couple more, and continue until you build up to 6 hours. That way your not flooding the tank with double the light all at once.