Malawi Mbuna Cichlids
Water temperature should be 23-28oC (73-82oF), so a middle value of 25-26oC
(77-79oF) is probably ideal. At the lower end of this scale, the fish may be less aggressive,
but also less active and less inclined to breed.
The general hardness in Lake Malawi is not as high as many might think - around 7 degrees GH. The carbonate
hardness is around 10-12 degrees KH, which leads to the higher pH values measured - in the region of 7.8-8.6.
Therefore, in an aquarium setup, the GH should be 7 or higher and KH ideally around 10-12, although these values are not critical.
pH is more important and should be maintained close to 8. Never allow the pH of a Malawi setup to fall below 7.0 and into the acidic range.
If your tapwater or other source is already
quite hard, you may only need to add a buffer to increase KH/pH. If your tapwater already has a higher KH/pH, then it
is probably ideal for Malawi cichlids which will make things easier - it may also be a reason to consider these cichlids
in itself, as it is generally much more difficult to lower the pH of aquarium water if you have hard alkaline
water and wish to keep softwater fishes.
However, if you do not have hard, alkaline water, there are several ways in which you can increase either the GH, KH/pH
(which are closely related), or both. There are various rocks (and substrates) which will help increase the hardness and
pH of the water, and these include various forms of limestone rock (especially the crumbly tufa rock) and materials such
as crushed shells or coral gravel, which can be placed in the filter.
There are also commercially available products designed to mimic to some extent the hardening and buffering salts found in these lakes.
If your GH is too low, you can use one of the cichlid salts to boost the general hardness and mineral content to the desired level. Use
at the initial tank setup and during subsequent water changes to maintain consistant hardness levels. After adjusting the general hardness,
you may need to add one of the buffer products to achieve the desired KH and pH.
Note that if you have soft water, you must not use normal salt (sodium chloride) in an attempt to replicate appropriate water conditions.
Common salt increases the overall mineral content of the water, but does not increase hardness or pH. So instead of making soft water into
hard water, it merely makes soft, salty water - which would be most inappropriate for these cichlids. Table salt, cooking salt and most
'aquarium' salts are based on sodium chloride. Marine salt does increase hardness and pH, but is still not an appropriate composition for
these freshwater fish.