Planted Mbuna Tank
Planted Mbuna Tank
Written by Friday, 16 July 1999 02:00
My mbuna tank (see photo above) has a capacity of 500 liters - 125 gals (measuring 150x50x65 cm). It is filtered by two external canister filters and two internal sponge filters (a total of 3600 L/h), and lighted by 7x40 W fluorescent tubes of various brands and colors. I always use two Penn Plax Ultra Tri-lux tubes and the others are either Penn Plax Tri-Lux or normal greenhouse lamps (PHILIPS Aquarelle or OSRAM Flora) to reduce the cost. The lamps are changed once every year, not all together but one every month. The average lighting is more than 0,5 Watts per liter. UV sterilization is also in line (two 8-watt units from Aquanetics) to the external filters and stay on for 8 hours daily. I also use a CO2 injection system, which consists of a 2.5 Kg (5 lbs.) CO2 canister, regulator and silicon tubing (the normal airline may lose as much as 50% of the carbon dioxide injected). There is a bubble counter on this system and a CO2 diffuser, which was later removed because I found a more effective way to increase the dissolution of dioxide in the water. I drilled a hole in the intake of the external filter and attached the end of the silicon tube connected to the CO2 cylinder. Thus, the carbon dioxide is forced to travel in the water stream for many meters, get in the canister where it is dissolved and then is returned in the tank. The gas is dissolved so efficiently that you can barely see any bubbles coming out of the filter outlet. There is also enriched gravel and continuous pH monitoring. Typical water parameters are Temp 26-30C (the latter in the summer when four ventilators are pointed parallel to the water surface to increase water evaporation and cool the tank a bit), pH 8.3 (before the injection), GH 10° and KH 14°. Maintenance routines include a 50% water change every week, and regular additives such as liquid plant fertilizer, aquarium salt, baking soda, and others. Among the fish species are Melanochromis auratus, Melanochromis chipokae, Melanochromis johanni, Maylandia lombardoi, Cynotilapia mbamba, Labidochromis caeruleus, Akanthopsis choirorynchus and Pterigoplichthys multiradiatus. Lately, a trio of Haplochromis nyererei was donated by my MCH teammate, Francesco. Plants include Echinodorus bleheri, Anubia barteri, Anubia nana, Cryptocorine willissii and Hygrophila corymbosa. Needless to say, there have been quite a few other species which were initially tried but they didn't make it, either because of mbuna consumption Egeria densa) or the water conditions. I feel that, despite the carbon dioxide injection and the fertilizer, most plants simply can't cope with the high mineral content of the water and the high pH. Amongst the ones which do, you must choose the ones which are not consumed on the spot by the mbuna or grow fast enough to outrun them. Once you solve these problems you can focus on aquascaping and pot the plants in an aesthetically pleasing way.
I think that the best advice with this sort of tank would be to take care of the fish and not the plants - this is rule number one and should be followed strictly. I do my CO2 injections with the eye on the pH meter. The starting pH is 8.2-8,3, the KH of the tank is 14° (which means a very big capacity for CO2 without dramatic changes in the pH) and I wait till the pH drops to 7,6 over a four hour period. Then I stop the injection and let the pH come back to 8.2 (it takes another 8 hours to do so). This is the normal day cycle. I always have heavy aeration with the internal filters pointing at the surface, even during the actual injection of CO2. When the lights are turned off an air pump goes on until the next day cycle. This way, any remaining is removed from the tank during the night. In any case, CO2 is absolutely essential for this kind of aquarium but you should be very careful not to overdo it. African cichlids come from a habitat where dissolved CO2 is very low and won't tolerate very high concentrations of this gas in their water. My approach doesn't seem to stress them (at least the species I keep) and it also helps the plants to grow at very good rates.
When the tank was initially started I used a mix of teralite / gravel 1:3. Actually it took 35 Kg of teralite and 100 Kg of gravel to get the 4 inch (10 cm) substrate I wanted. I used some plant pellet fertilizer buried next to the roots (Tetra Crypto tablets) for the first 6 months after setup and then stopped it. The plants in the tank will not thrive. They will have a steady growth, which is enough to compensate for the consumption of leaves by the mbuna. Mbuna when fed correctly should always starve in order to be active, spawn and display their beautiful intense colors. The recommended feeding is small quantities every other day. This means that in the "non feeding" day, almost all mbunas will attack algae and plants. They will eat Egeria densa (except the top of it, which is regularly replanted when the rest of the plant is consumed), will eat Amazon swordplants (almost every mbuna will nibble on it, therefore this plant is not to be kept in such a tank) , Vallisneria gigantea (yes, they will eat that, too, even the runners), Hygrophila corymbosa (which grows much quicker than mbuna can consume). They will even nibble on anubias (to a far lesser degree). The only plants they will not attack are Cryptocorine and Nymphaea lotus.
If such a tank is to be aesthetically pleasing and safe for the fish, one needs to spend much more time on it than with a regular tank. You must remove eaten leaves at least twice per week and clean filter intakes every other day. Strong filtration is essential which means at least 4-5 times the water volume per hour. A much stronger filtration rate (10-12 times the water volume) is highly recommended if carbon dioxide injection is to be introduced. Better safe than sorry. If you are not going to use the extra - sophisticated (and rather expensive) pH controlled CO2 delivery systems you should also pay attention to the manometer of the gas cylinder. When the pressure in the cylinder drops significantly, you should get your cylinder refilled. Do not try to use all the gas because when the pressure gets very low in the cylinders, most manometers tend to release all the gas at once and it doesn't take long to lose all the fish from suffocation. Once, I forgot to check the manometer for over a month and then, when I came back home, I had to manually stir the water for 30 minutes to get the gas out of it. Unfortunately, one of the mbuna didn't make it while all the others remained lethargic at the bottom for another 3 hours. It goes without saying that an established biological filtration is of outmost importance. All plants should be planted with their pots (if supplied) or else secure them in place with rocks, big enough for the mbuna. It is even better to create "rock pots" fill them with gravel and whatever else you want to add (teralite, laterite etc) and then add the plant. It is a very good thing if you can decorate your tank before adding the fish. If you can allow some time for the plants to establish it will pay off later since the growth will be enough to compensate for eating. Another point is to use fast growing plants, able to survive and grow (not thrive) in a pH around 8 and a GH around 10°. The exception is anubias, which are not eaten so they will grow in peace, they will even produce flowers every now and then. Intense photosynthesis will be observed for about 4 hours (see photo below:
You should also take into account the need for shelter for your mbuna and plan your tank correctly from the beginning. Please note that this is not the only setup that will work with plants. This setup guarantees that the selected plant species will grow and the overall look will be like a "Dutch" aquarium (see photo below):
Another setup is used for Malawi Haps in a 1.300-liter tank - also planted. Here I kept things simpler. I selected plants already existing and growing in my 500 liter tank (accustomed to extremes like pH=8.3 and GH=10°) and used them in the big tank. There is no carbon dioxide injection, not much lighting (usually less than 0,25 Watt per liter, Hagen Aqua Glo tubes) and no fertilizer in the substrate, which is plain sand. Take my word for it. Anubias will be fine, Cryptocorines will thrive, Hygrophila corymbosa will grow slowly but steadily and will finally create a small "forest" while Amazon swordplants and Vallisnerias will be eaten all the time (this has to do with the particular species I keep I guess). Adding many Hygrophila corymbosa in a circle will create a beautiful shelter, which will last for a year or so before it needs cutting and replanting. You can compare the two photos below and see how much the plants will grow in one month under the conditions described in this article. In 2-3 months the whole part of this tank will be filled by this plant. Unfortunately the plant grows to about 60 cm in height so a big tank is also essential if you are looking for this effect. It should be observed that the mbuna did not touch these plants. This will not happen with all plants or with all mbuna. The hobbyist should first test some plants and then use the ones his specific mbuna didn't touch.
The 1300 liter tank is running for 15 months now and all plants are doing well. A tip for interesting aquascapes is to locate the plants between rocks. This gives a far more natural appearance (and the Africans can't remove them). Anubias will stick on rocks and create interesting spots with juvenile fish finding shelter among the roots (see photo below):
The non-mbuna tank is inhabited by Nimbochromis polystigma, Nimbochromis livingstoni, Nimbochromis venustus, Cyrtocara moorii, Chilotilapia euchilus, Buccochromis nototaenia, Aulonocara stuartgranti, Protomelas taeniolatus, Protomelas steveni Taiwan reef, Placidochromis electra, Copadicrhomis azureus, Sciaenochromis fryeri and Nyassachromis boadzulu. Scavengers include Akanthopsis choiroryncus, Pterygoplichthys multiradiatus, Synodontis decorus and Synodontis multipunctatus. Plants include Hygrophila corymbosa, Anubia barteri, Anubia nana, Echinodorus bleheri and Cryptocorine willissii. My Valissneria gigantea has now been consumed to the roots.
In the following photo, there is a carrying Melanochromis auratus (she released two days later) hiding in the dense vegetation of my tank (here is a Cryptocorine species, while the plant in the foreground is an Amazon swordplant - before being consumed to such an extent that made it a visual nuisance). In this sort of dense vegetation (which can very nicely substitute rockwork in your tank) the fish feel secure and relaxed since they can easily avoid the other females or males.
If you watch this picture closer you will even see a 40 days old Melanochromis chipokae to her right. The small fish, in an empty tank would be readily chased if not killed on the spot by the carrying mother or during the spawning procedure. Here it can stay within 5 cm from the mother and be invisible. Bear in mind that these are two of the most aggressive species available in the hobby - most aquarists clearly avoid them for community Malawi tanks. Both, when grown adults, will fiercely attack fish double their size. That is the reason for many hiding places in such tanks and plants provide lots of them. You will need the rocks because most mbuna will just choose them for spawning but you don't need them as hiding places.
You may arrange your tank chemistry to suit that of your fish and let the plants find their own way. You will be amazed to see how easily some plant species adapt to these conditions. Carbon dioxide injections should be performed very carefully. The elevated pH of the tank is needed for the fish therefore a continuous supply of CO2 is not recommended. Heavily planted mbuna aquariums are the exception rather than the rule and this is because vegetation in their original habitat is not dense at all. However, the mbuna most of us buy are born in captivity and, as a hobbyist once said, "they wouldn't recognize Malawi habitat even if someone dropped them in the Lake". This is true and I can ensure you that the fish will live happily and spawn readily in such a tank. Survival rate will be also high since the fry can hide for the first couple of months when they are more vulnerable, still enough food will come to them because of the water movement. It is not uncommon to get 40% survival rates even in this crowded tank.
Another reason for a planted aquarium is the removal of toxins, most importantly nitrates. Though biological filtration transforms ammonia to nitrites and then to nitrates (much less toxic than ammonia) still there is nothing to remove nitrates from the tank (hence the need for frequent water changes). The addition of plants may reduce the frequency of water changes since plants will use nitrates for food. Another point which should be stressed is that higher plants will compete with algae for available nutrients and usually (if the plants are healthy and growing) they will not allow algae to thrive. I may be lucky in this aspect. I have been observing my lava rocks and I can see fresh algae all over them (this particular region of the tank is not covered by plants, so light can reach the rocks). However, I have not experienced any algae problems for the last two years. Usually, I use a razor to remove the algae from the glass and then use the magnetic scrubber to remove new algae every two weeks. It may take as much as 7-8 months until I have to use the razor again to remove algae from the lower part of the glass (the one close to the gravel).
Sometimes, when I discuss this sort of tank with fellow hobbyists I have the feeling that most of them regard planted tanks a possibility limited to big tanks only. Nothing can be further from the truth. All that is important is the desire to create this combination. I have included a picture of my (relatively) small raising tank which was recently decorated with live plants. During my regular trimming of the main tanks, I decided to use the plant cuts to create a special environment for this tank. The tank is a 140 liter all glass tank, without any canopy, no light fixtures, no external filters. Just an air pump, an internal sponge filter (cleaned every week) and a heater. The lamps are supported on the tank itself. Yet, with some natural elements and no cost at all (sand collected from the beach, rocks collected from the seaside and plant cuts from other tanks), I managed to create the sight you can see in the picture below. This tank houses Malawi haps which are raised there till their size is big enough for the 1300 liter main tank. The inhabitants are 7 Fossorochromis rostratus, 3 Cyrtocara moorii, a male Nimbochromis polystigma and a male Copadicrhomis azureus. Plants include Anubia sp. and Hygrophilla corymbosa (my preferred plant because of its quick growth). It will take you less than an hour to decorate such a tank and you can always add a plant or rock if needed. If it can work in such a "Spartan" tank, just imagine what you can create in your main tank.
As a conclusion, it can be said that a planted mbuna tank is possible. I can't say it is easy - just possible. However, the result is really beautiful and one can combine the best of two worlds. The relaxing vision of a planted tank with the intense colors and exceptional behavior of the mbuna.
| < Prev | Next > |
|---|