Thanks all for the nice comments.
@framerguy
Thanks Greg .... as you wrote, it is a lot of resarch necessary but also a lot of try and error. With a dive in the Red Sea I discovered many years ago this offshore \\\ "Miniriff \\\", thus my aquarium should look once.
I think it is in the meantime not very far of it. I am very contented, in any case, with the present result.