An emotional moment
I must admit that the visit to Lake Tanganyika was a very emotional one for me. Tanganyika cichlids were my very first aquarium fish. They really excited me 40 years ago and they still fascinate me. And when you stand on the shore of the lake for the first time and look beneath the seemingly endless water surface with your diving goggles, it almost brings tears to your eyes. Those fish I once struggled to afford from the pet shop are there swimming around. You can see the Tropheus, Lamprologus, Julidochromis and Telmatochromis species as soon as you look in. The water is as clear as any aquarium owner would wish for, and, at 28-29 °C, it is also pleasantly warm.
Lake Tanganyika is not exactly on our doorstep, of course, and only a few years ago the journey was very time-consuming. Today there are 8.5-hour direct flights from Germany with Condor to Arusha in Tanzania for €900 - Emirates even offers flights via Dubai from €650. From Kilimanjaro Airport near Arusha, a domestic flight takes you the 900 km to Kigoma at Lake Tanganyika. I recommend the Hilltop Hotel directly at the lake, very nicely situated on a small cliff. There is a small path from the hotel down to the water and snorkelling is worth your while without you having to go a step further!
The biodiversity
Even in the shallow depths of between one and five metres we can see so many species of fish that we forget the time and get a nice sunburn. A full, thin diving suit is highly recommended to avoid turning crab red like we did. We find various biotopes within a radius of only 200 metres: Sand flats with beautiful thread-mouth brooders (Cyathopharynx), some spiny eels, snail cemeteries with their small shell dweller inhabitants (Neolamprologus species) and smaller rocky reefs with Tropheus and other Lamprologines - sometimes in incredible numbers. Militant animal rights activists would probably sue Tanzania for overstocking. But the natural animal population is not regulated by laws, it’s regulated by the number of retreats and the food supply.
With a bit of luck, you can also observe somewhat rarer species in the shallow waters. Your chance of doing so increases with every hour you spend there. I had the opportunity to spot large Lepidiolamprologus elongatus with fry. It's always fascinating to see how the parents with that extra dose of parental motivation put every predator to flight – humans included. Or you can meet the largest fish in the lake and second largest cichlid in the world, the Boulengerochromis microlepis. At 70 cm, it is an imposing sight and quite frightening when it attacks the diver or snorkeller defending its fry. But unlike triggerfish in the sea, it does not bite pieces of flesh out of our bodies!
Leave some time for the "boring" sandy areas. In Lake Tanganyika there are many species that have specialised in this hostile habitat. If you look closely, you can observe that there are burrowing fish accompanied by clever chasers. Digging releases small organisms that the chaser can eat. In return, the chaser watches out for large predators approaching, which the digger does not see immediately, as it often dives with its head in the sand. A real symbiosis worth seeing!
It is also worth snorkelling in the lake at night: the shrimps only come out after dark, the spiny eels go hunting then and catfish also make an appearance. The warm water means that we don't cool down much at night and can still go on extended snorkelling tours.
The water values
Everyone definitely needs to take a few water tests along. The special water chemistry of the lake has to be seen with your own eyes: At 16-18 °dKH, the carbonate hardness is higher than in almost all other tropical waters on earth and also higher than the general hardness (10-11 °dGH). This is due to sodium carbonate compounds, which increase the carbonate hardness but do not count towards the general hardness, as they do not contain calcium or magnesium. The pH value is 8.8 and 9.0 with a conductivity of 645-690 µS/cm. You can safely leave the water tests for nitrite, nitrate and phosphate at home. In natural waters, such "problem substances" are only found when humans heavily pollute the waters.
My favourite fish - the Cyphotilapia frontosa
But I haven’t yet been able to discover my favourite fish, the Cyphotilapia frontosa or front cichid. This species lives in large rocky reefs from a 25 m depth. If you have taken a free-diving course (apnoea diving), you can reach this depth by holding your breath. All others have to breathe bottled air. Unfortunately, it is quite tricky to rent tanks in Kigoma, so we organised all this in advance for our JBL expedition and even brought eight scuba tanks with us. The Hilltop Hotel arranged a boat and so we took a 20-minute boat ride to a spot where Cyphotilapia were supposed to live. And indeed, we saw the first animals from a depth of 22 metres. The smaller females stayed very close to the rocks at the bottom. The large males hovered majestically in the open water above. The sight was breathtaking: the frontosa males were a good 40 cm long and an incredible sight. Due to the depth of about 30 metres, the dive time was limited to 15 minutes so that we did not have to make any stops on the way back to the surface (no-stop time). In case of a diving accident, there would have been no pressure chamber available and so safety had to come first. But even these 15 minutes were enough to observe the frontosa a little, take a few photos and just enjoy the presence of these beautiful animals!
Travel tips
Kigoma/Tanzania on the north-eastern shore of the lake is an ideal starting point for us aquarists because of the airport and the Hilltop Hotel (approx. €100 per night/double room with breakfast). The passport must be valid for at least 6 months beyond the travel date. You need a visa and you can apply for it online from the Tanzanian Embassy. The best time to travel are during our summer months and January-February. Daytime temperatures are around 29 °C. At night it cools down to 20 °C. Get information about the vaccinations currently required from a tropical institute. We advise: typhoid, polio, meningitis, hepatitis B and rabies when handling land animals. Good prevention against stings with e.g. No Bite is always advisable in the evening hours. If you want to spend some more time by the sea after the Lake Tanganyika trip, you can take a domestic flight to Zanzibar and enjoy the island with its coral reefs. There are also direct flights from Zanzibar to Germany.
On the subject of the risk of contracting a disease or infection, Lake Tanganyika also has good news: If you avoid the shore areas where many people (locals) bathe or where the rivers flow into the lake, there won’t be enough snails for the schistosomiasis pathogens’ life cycle. The biggest risk at the lake will be sunburn!