Need some advice!

That is crazy about the lack of evaporation. I am in the 2 gallon a day club and that's on a 75 with a 20 refuge and 20 sump. My next project is a auto top off.

 

Well you have to remove those tops LFS love to sell that carp the water is sealed in and so is all that CO2 and Nitrogen Gas thats the reason for the Nitrates there is noway for the gas to escape or be exchanged for oxygen you remove the tops add some pumps to agitate the surface and then come on and tell use what the evaporation rate is But the tops are killing the animals take that for what its worth . Put a plastic bag on a dogs or cats head and people would be all over you not to mention the animal cops. Those glass tops on a sump less system is a plastic bag on the head ):

 

Ok Tangster i am not going against you but I have a small problem just taking them off. I use a Emporer 400 and I think that the splash will be too much and also I don't have a canopy and i am not a carpnter so I can't find one for my aquarium. So what should I do?