It is freshwater and because he is such a behemoth anything we put in there will get dug up if it isn't weighted well.
This might be a little difficult to picture but I'll try to paint a picture. My basement has a finished recreation room. That room is part of an addition to the house so the inside wall is against the original foundation. Part of that foundation wall has been removed (it has been reinforced).
So here's the plan; build the tank into the wall and use the opening in the foundation wall as access to the back. I have access to water, electric, and extra space in the room on the back of the tank (it's a laundry/workbench/furnace room). The original basement floor is about 15" higher than the floor in the Rec room (the viewing room).
I plan on doing all the work myself. I did my own plumbing in the house and am skilled in electrical work. I bought the house less than a year ago and already built a brand new bathroom in the basement.
The access in the back will be where I plan to put the filter, do the water changes, and deal with the less attractive equipment or whatever. I like the idea of a storage bench by the tank. I have little cousins, nephews, & nieces that would stand on a bench to see into the tank.
As for the design of the room… I plan to basically redo the whole Rec room. It currently has ugly paneling, poorly done tile, and I already tore down the drop ceiling. I'm going to Sheetrock everything, so the tank wall will use the same rock as my bathroom to deal with any water.
What do you mean a "double see-thru?" Would that be a paned window in front of the tank, or were you thinking of viewing from both sides?