Malawi Mbuna Cichlids
In general, a mixed mbuna community should not really be attempted in tanks less then 3ft / 1 metre long (about 25-30 gallons), and opting for
this minimum size will restrict the number and species of mbuna that can be kept, as well as making it more difficult to maintain water quality.
A tank 48 x 15 x 18" / 122 x 38 x 45cm (approx 40 imp gal/180 litres) would be a better 'minimum', and larger tanks of 5-6 ft (150 - 180cm)
will allow for a more impressive display.
One of the reasons a larger tank is required is the way in which these cichlids are normally kept in order to minimise specific aggression.
They are naturally territorial and aggressive fish, and dominant males may become "hyperdominant" and take over the whole tank as their own
territory if they are stocked very lightly. Heavier stocking diffuses aggression among more individuals and means that it is more difficult
for any one fish to take over a large territory; it also minimises the chances of any weaker fish being specifically victimised constantly.
A heavier than normal stocking level can work very well in larger tanks.
This impressive tank can be seen at
the Blue Planet Aquarium, Cheshire, UK.
Due to the aggressive temperament of males, the ideal stocking ratio for each species would be one male and 2-3 (or more) females. However,
in practice, this may be more difficult because some mbuna are difficult to sex, especially when juveniles.
A consequence of this heavy stocking is that frequent water changes (and very good filtration) are required.
Regular water changes are essential to keep the levels of nitrate low and the water quality high. Luckily,
Malawi's seem to thrive on frequent large-scale water changes, and it is recommended that a minimum of 25%
every 2 weeks is changed - 30-40% per week is not unreasonable in a well-stocked tank. Remember that the
larger the percentage of water you change, the more closely matched in terms of temperature, pH and hardness
it should be to the tank water.
Filtration and circulation
It is recommended that you exceed the normal filter ratings when setting up a Malawi tank. When fully stocked, at least two filters
will be beneficial - ideally a combination that provides good biological and mechanical filtration, such as an external canister filter
and an internal or hang-on-tank power filter.
Two filters, and/or an additional powerhead or airstone(s) will help to improve water circulation and maintain a high oxygen content
in the water. Good circulation also means improved mechanical filtration, and less debris left on the tank floor.
With no requirement for live plants (see below), the lighting in a mbuna tank need not be too bright, and certainly bright lighting should
not be combined with a light-coloured substrate, as the glare will tend to make fish more nervous, and show paler colours. On the other hand,
the intense colours of mbuna are best seen under reasonably bright 'white' lights. Avoid lights with a lower colour temperature which cast a
yellowish light. 'Warmer' soft white lights are best combined with a brighter white light or a blue tube. Brighter lighting will encourage algae,
but this should be seen as a good thing, as it will provide some of their natural nutritional needs.
There are no higher plants (just algae) in the natural home of the mbuna, so plants are unnecessary in a mbuna tank, and although they
will not necessarily be eaten, they will probably be constantly dug up by the fish. Also, many plants do not do well in hard and alkaline water.
A few hardy varieties may survive if you wish to include plants in your setup.
The natural habitat of the mbuna is a rocky landscape forming many caves, and you should attempt to duplicate this to some extent in
the mbuna tank. It is not unusual for most of the back and side walls of the tank to be devoted to rockwork in a Malawi setup, leaving
some open swimming space in front.
The choice of rocks is not so critical in a Malawi tank as it would be in an aquarium for softwater fish, where rocks like Limestone,
which leach hardening salts that raise pH, would be a problem. In a Malawi tank, such rocks can actually help to buffer the pH to the
higher values required, so the choice is less limited, and could include limestone, slate, tufa (a very crumbly form of limestone),
lava rock and ocean rock/holey limestone - which is very popular and provides lots of little niches, but is less natural looking if
you wish to create a more genuine looking biotope tank.
The choice of substrate is not critical, as long as you avoid sharp gravel (such as crushed coral gravel), which might injure the cichlids
mouths when they attempt to dig (if crushed coral is used to help buffer pH, place it in bags in the filter). Standard pea-sized natural
aquarium gravel is fine, or any suitable type of sand.