I have changed the plan to a 16'L x 6'W x 4'T (waterline is 36") concrete tank with 10' viewing window. Total size including the attached sump/filter is 20' x 6'W x 4'T (about 2500gal). The indoor pond project was cost prohibitive, just the solarium was going to cost $100,000! There was an issue with asthetics also. I'm not so sure that the indoor pond idea would have been as astheticly pleasing as a my current plan. The tank will be poured as a single container with a divider wall for the sump filter area. Electricity will be less than $200/month. The total cost for the tank, lighting, pump ect. will be about $20,000. I have the whole thing worked out fairly well right now. I'll try to post my plans within a few days (i'm at work right now).