I'm not too worried about finishing the rest of the project with the livestock in the tank. In my opinion, they are safer in the tank while work is going on than they would have been in the tubs where there was much more exposure to construction debris. Ideally, I would have liked to have everything completed before moving the livestock in, but since they were in open tubs, I felt this was the best course of action.
The tank came with acrylic covers to virtually seal it off, but other than hanging the lights, everything inside of the fishroom is complete. The areas where the trim is going has already been sanded, so I'll get that up soon to seal off the tank before any sanding or painting goes on. The viewing room and the fishroom are well-ventilated, so I'm not concerned about paint fumes.