Arches catagory
This is a catagory that seems classic due to the memories of all of us as children make such things for our fish to swim through . I am training one of my tanks with this design. Here are some great examples:
Shaner28 I believe that on that pfoto are these fishes:
Trigonostigma heteromorpha "black"
Puntius titteya
They're not all that common, they're generally seen as perhaps either a bit tacky, I'm thinking plastic castles or something that are of such a large scale they would more likely be a public aquarium exhibit. I've seen some, they're rarely pretty though. It depends on what you mean by "an old ruin". But yes, typically, as a hobby we try and shy away from anything man made, "nature" is the aim of the game.
This one belongs to a seriously talented guy from Australia. I think I'd call this sub-category 'flouro-dutch'. One of the best tanks that I have ever seen.
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