Well, being my usual fussy self I've been umming and ahhing for ages over this tank, and I've finally decided that I just don't like it.
Its weirdly shaped, its very tall, it has a rather poor surface area and considering how little water it holds, it takes up quite a lot of space! But I've grown quite keen on the idea of a nice little tropical tank, sooo... I've bought a replacement!

It's a bit bigger (about 28 litres) and is the standard rectangular shape (18x10x10 inches), which I much prefer! I've transferred the contents of the 21 litre to the new tank (filter, gravel, plants etc) in the hopes that the cycling process won't be knocked quite all the way back to square one... but I'm in no great hurry so I don't mind if I have to start cycling again from scratch.

In response to the siamese fighter discussion - If I were to get one I would definitely only get one. I've heard that males have to be kept with a minimum of three females coz they harass the females so much - and I certainly don't have room for four of them!
Having said that, I really do prefer the idea of a small shoal of really tiny fish, like the microrasboras that Pleccy suggested or endlers maybe

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