Thanks for the comments all.
The windows is made from 40mm acrylic, welded at the corner.
robroy, to be honest, I've no idea how the window will deal with the winter. I will be running large airstones a few inches from the surface by the window when the temps drop low enough to try and stop any ice building up in that area. I do have a 3kw pond heater, but I don't want to run it if I can avoid it.
The windows is made from 40mm acrylic, welded at the corner.
robroy, to be honest, I've no idea how the window will deal with the winter. I will be running large airstones a few inches from the surface by the window when the temps drop low enough to try and stop any ice building up in that area. I do have a 3kw pond heater, but I don't want to run it if I can avoid it.