As the one who chose the over-arching title for the thread to concentrate the kind of images it currently contains, I would agree that it's best to keep an open mind: You decide if something fits into this thread - who're we to tell you off if something appears "not suitable"?Let's keep it as easy as possible. We're no judges on a contest panel. I'd prefer to take the two criteria of the thread name in the widest understanding possible. Minimalism in the sense of reduction to the smallest amount of whatever and abstract in the sense of everything that's not concrete. And let's the posts show us who has had a creative, brilliant, cute, astounding moment when he released the shutter and leaves us just exclaiming *wow*.
As to your doubts, Jens, I had no problems with your post seeing that this (concrete) fish is reduced to its head only. So no abstraction here but definitely minimalism. BTW, I love the colours.