50g cover help?

i recently transferred my reef from a 30g to a 50g and all is great but i do not know the best way to cover my tank so that im not loosing of 10g a week from evap like i am now i cant put a standard hood on becuase of the light mounts on the side of the tank... tips or suggestions will be appreciated

 

Water evap does take its toll but I will say I had class covers on my tank and I couldn't keep up with having to clean them every other day due to salt ceep. But if you still want covers most LFS carry glass covers with plastic hinges in between you can buy.
I also took mine off to get better gas exchange.
The problem I see with using a standard hood would be it will narrow the light going into the tank.

 

If you try to prevent water evaporation, you will get overheating in your tank, or water condensation on the tank tops. Either way, it is evaporating in some sense. With a 50G tank, you should top off about 2G a week under normal circumstances. Unless you live in an arid area, it shouldn't be too bad. I top off about 3-5G a week on my 150G and 1G on my 20G