Central African blackwater biotope

[Margit]

Jambo,

two months ago, I set up my tank. The measures are 120cm x 80cm x 50cm (nominally 480 litres / 125 gallon). The tank is open top; it is meant to recreate a Central African swamp stream.

I partitioned off a 25cm high section along the back panel, filled it with garden soil and planted Cyperus alternifolius. Some of the stalks are pushing 2 meters. There also are Salvinia, Pistia, some Echinodorus, a single Anubias nana, Microsorium and Java moss. The Echnidorus will be replaced once I find more Anubias or Bolbitis. I also tied Syngonium and Epipremnum to pieces of wood that stick out of the water. I like the way these plants send their roots into the tank...

Leaf litter (guava, mango and Indian almond) has turned the water dark and I hope acidic. The water in Nairobi is very soft; unfortunately, test kits are not available - so, I have to trust in my experience (I had my first tanks more than 40 years ago), intuition and regular water changes....:eek3:

There is no equipment other than a heater (set to 26C), a single Grolux-type fluorescent (I rely mostly on sunlight) and a Powerhead for circulation.




Currently, I keep 4 Polypterus delhezi (20cm - 30cm); a few feeder guppies also remain in there. I still hope to get Ctenopoma acutirostre, Tetraodon schoutedeni and a pair of Hemichromis.



The Polypterus feed on dried omena (Lake Victoria "sardines); it took them weeks to figure out that guppies are food...erv:

Greetings from Nairobi

Margit
​

 

[rufioman]

Dude...whoa. I don't even know where to start with how sick that tank is. +1 for epicness.

:cheers:

 

[Belltrain]

nnoommyyggoosshhh so epic.mg:

 

[Rbishop]

Great set up!

 

[Fish Bowl]

Nicely done!

 

[platytudes]

Amazing! Looks like a public aquarium display Just stunning...props to you!

 

[jm1212]

very cool setup!

with no filter though, I am curious as to how your parameters are doing.

 

[Margit]

Hi,

thanks for the positive feedback..:cool-1:

I tried to set up the tank in a way that (almost) no equipment is necessary. The Cyperus is really amazing when it comes to depleting the water of nutrients. That's why it is used in wastewater treatment. I had Cyperus in a pond and it kept the water clear and algae-free for years. The pond was stocked with guppies and tilapia (my guess is Oreochromis mossambicus). Even the submersed parts of the stalks provide an ideal surface for denitrifying bacteria. Plus, bringing in organic soil meant I had all the bacteria in sufficient quantity right from the beginning.

I looked for test kits...but it seems that when they were stocked, they expired before anybody bought them... so the shops didn't bother to import more. So, I just have to go by the evidence:

• The water is clear
• I have no algae problems whatsoever (there are a few on the glass, but none on the wood, rocks or plants)
• The fish show no discomfort at all; as a matter of fact, they are thriving and showing signs of courtship behaviour

I wanted to create a set up that could be sustainable even when electricity fails (pretty common here). A canister filter would be worse than useless after a power failure... it spews toxins into the tank. The longest period I've ever been without electricity in Africa was 9 months, when a substation blew up in Lagos... Since the tank has been set up, I experienced only one 24 hour power outage.

The tank needs to function like a natural pond. That also explains the dimensions - the tank is much deeper than high, providing a large surface area for gas exchange. Also, the tank is in a very bright spot, receiving sunlight from two very large windows. The fluorescent is more for my benefit, so I can enjoy the tank in the evenings...

Here are some pictures of the way I set it up:





I do very little maintenance. Every other day, I clean the tiny sponge at the intake of the powerhead; I water my houseplants with water from the tank - I then top it off with tap water. So, I have frequent small water changes. Once a week, I change 10% of the water.

When I started thinking about setting up a tank that would be low tech and sustainable in an environment, where you can't take a steady power supply for granted, I found my old books most helpful (those originally published in the fifties and sixties, before the hi-tech craze started; e,g, Frey, Sterba, etc.). The Walstad approach was too limiting... I never wanted tiny fish... I still want cichlids... :grinyes:

Greetings from Nairobi

Margit

 

[jpappy789]

Nice, love the emersed look.

 

[Margit]

Hi,

just a small update: I got a bit tired of the tank being seemingly lifeless. The Polypterus are active only during feeding times; the remainder of the day, they are hidden in their caves. So, when my lfs had blue Congo Tetra, I got a group of 15. They are still tiny, between 3 and 4 centimetres. Just about the size of the dried fish I feed my Polypterus :eek3:

They spent their first night and none were lost. I hope they grow quickly, though... They are still too small to show any colour...

I experimented with my BlackBerry... so, here's a short video.

http://www.youtube.com/watch?v=uNk4BD7SiFo[