Plans for an attractive Orinoco River Basin Biotope Aquarium

The presence of a blank canvas thanks to my new Aquatlantis tank encouraged me to search the web for ideas on aquarium design which is when I came across the amazing world of aqua-scaping. The landscape style designs have astounded me and I’d love to build something along these lines, but don’t think I quite have the patience, ability or time for maintenance that would be needed to keep such a landscape looking at its best. I have however been inspired by the combination of art and nature all confined in a watery cuboid and want to see if I can create something a little more impressive than my previous attempts. I also like the idea of biotope aquariums with fish and plants all coming from particular geographic region so now want to combine the art of aquascaping with the science of biotopes to create an attractive biotope aquarium based loosely on the Orinoco River Basin.

I may be getting ahead of myself and being a little too ambitious, but here are my plans so far.

Tank: 102x40x40cm 188 litres
Filter: Internal Biobox 2 filter
Lighting: Aquatlantis H2O LED System 43W
Our local water is very soft and neutral with a pH of 7.0


This is probably my greatest challenge, but I like the sense of depth achieved by design with a ‘path’ leading the eye into tank and also like designs with a certain amount of height to the hardscaping which seems to add more depth to the overall effect. I’m therefore hoping to build one side of the tank up with some large rounded pebbles to create a terraced ‘river bank’, along with some nice bits of root-like drift wood coming from the ‘river bank’. The river bank will be planted with a midground pant and possibly some background plants behind them. This river bank will hopefully slope down to a path that starts low at the front of the tank and narrows as it recedes and rises to the back of the tank. I’m hoping to further enhance the sense of depth by lining the path with larger pebbles at the front of the tank and pebbles that reduce in size towards the back. The other side of the tank will be a lower more rounded mound planted with low growing plants to create some free open water above it.

I’m hoping to use locally sourced beach pebbles for the structure and a complete, dark brown substrate such as Colombo Flora Base as a substrate.

I have a few questions that I need to research regarding the hard-scaping.

1. Is the Colombo Flora Base any good? How much of it would I need for a tank of this size?
2. How do I keep the slope of the substrate from shallow at the front and middle of the tank to deeper at the sides and back of the tank in place? Whenever I’ve tried to do this in the past it all ends up as a single layer of uniform depth. I may be able to do this by holding it back with the pebbles.
3. I’d like to keep the ‘path’ free of plants and will probably use a lighter coloured general aquarium gravel for it (probably some from my existing tank that will help cycle the tank when I first set it up). I have the idea of building the receding path out of bits of slate and then covering this with a thin layer of the gravel. Hopefully this would prevent plants from growing in the path as there wouldn’t really be any substrate for them, but I’m wondering if this would create any other problems that I’ve yet to think of?


I’m hoping to stick loosely with the Orinoco River Basin Biotope here and want to keep things fairly simple. In the past I’ve always gone with lots of different types of plant but will try to restrict myself this time. I was thinking:

  • Echinodorus sp. as midground plants on the river bank slopes
  • Echinodorus tenellus as foreground plants and on lower mound side of the aquarium
  • Also, possibly some Myriophylum as a background plant and maybe to hide the filter box if necessary.

I need to research them a little more to make sure they’ll be OK in my proposed set up. It may be that they’ll need CO2 to grow well in which case I may need a rethink. I might like a specimen plant somewhere as well – but I’m not sure what yet or if its a good idea as it may just be me getting carried away as I like plants!


Obviously I’ll increase the stock of fish over time but would like to end up with something along the lines of the following, again sticking loosely to the biotope idea but trying to create some interest too.

  • Pencil fish – Nannostomus sp. (c.20)
  • Hatchetfish – Carnegiella sp. (6)
  • Cockatoo Dwarf Cichlid – Apistogramma cacatuoides (1 pair)
  • Blue Ram Dwarf Cichlid – Mikrogeophagus ramirezi (1 pair)
  • Otocinclus (6)
  • Corydoras sp. (6)
  • Peckoltia sp. (1)

Sounds good to me.

Although an external filter rather than the internal one would be nice, just to get it out of the tank as filters aren’t particularly attractive. Some CO2 might be necessary in order to grow the plants I want, and some nice backlighting might add to the overall aesthetics too.

This project will take me a while so I’ll be working on it over the next few months, but writing my plans down like this help me to formulate them better. It also gives me a chance to share them and hopefully get feedback from those more experienced at aqua-scaping, so please let me know your thoughts on these ideas as I’m not averse to changing the plan in order to improve the overall effect. In fact, the plans will no doubt change once I actually get around to working on it anyway.

1 Response

  1. mum says:

    Now I know why mine never looks as good as yours!

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Alan Cole

Alan is a Freelance Website Designer, Sports & Exercise Science Lab Technician and full time Dad & husband with far too many hobbies: Triathlete, Swimming, Cycling, Running, MTBing, Surfing, Windsurfing, SUPing, Gardening, Photography.... The list goes on.

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