Text and Photo by Paolo Salvagiani, translated by Francesco Zezza
The genera Eretmodus, Spathodus and Tanganicodus are members of the Eretmodine group. All members of the group are cichlids endemic to Lake Tanganyika showing similar physical and behavioural characteristics. A total length between 7 and 10 cm (about 3 to 4 inches) is attained in the wild, and because of their body shape/swim position, they are known, in the english speaking environment, by the common name Goby-cichlids. In the wild, they live in extremely shallow water along the shorelines where the oxygen level is extremely high because of the continuous water movement. The Eretmodus, as well as other Eretmodines, feed on algae that, due to high lighting, grows quickly and abundantly on stones. According to some ichthyologists, these fishes may be split into different species in the future. Remarkable differences in the shape of the mouth and teeth can be easily detected in fishes coming from different areas of the lake. Local morphs differ because of the colours: blue dots on the head and body can vary in size (or not be present at all), while overall body colour may vary from yellow/greenish to brown/reddish with the latter specimens generally not showing the blue dots.
A few years ago, I got six juveniles of Eretmodus cyanostictus “blue spots”, chosen because of their bigger and brighter blue spots: absolutely nice fishes (see pic). According to Mikael Karlsson of Africa Diving (cichlid exporter from Tanzania), relying on a pic I sent him, my fishes are possibly a “morph” coming from Isonga, in central Tanzania, south-east of Sybwesa.
Regrettably, during the trip home (from Germany to Italy, btw!), one of the fish passed away. Once at home, all “survivors” were released in a 650 lt (about 170 US gals) tank where other Tang cichlids were already living: a group of (fifteen) Cyprichromis sp. ”Kitumba”, few Ophtalmotilapia boops “neon stripe - Nkondwe”, plus some lamprologines. In a very short time, my five Eretmodus started to show their real “temper”: extremely aggressive among each other, not caring about the other tankmates at all. Despite the room available, there were, in my opinion, more than enough fights. They got on “happily” and in a few weeks I found another fish dead (to my sorrow!). It ended with four fishes living, one by one, in the four upper corners of the tank! Then, step by step, eventually two of them started to live in the lower part of the tank, one from the left the other from the right edge, with two others still carrying on in the upper part of the tank. Despite their bad temper, looking at them scraping algae was interesting (and amusing), mostly in summer (the tank is open and gets natural light from above): the blue dots were incredibly shiny!
A pair of E. cyanostictus spawning
It took me two years to spot some spawning attempts between the two dominant fish, but the pair did not do thier “homework” that well, and the first five/six or so, spawnings were fruitless (with the eggs spit/swallowed/unfertilized). I started to think my fish were ALL females until in late summer when things eventually started to go as expected, with holding lasting more than four days. I started to hope to get some fry. After twelve day of holding, a new milestone was in sight: the “change of carrier” (Eretmodus are oral, biparental egg-carrier). To my surprise, none of the members of the pair looked as though they were interested in the matter! Anyway, to make a long story short, and despite all of my worries, the exchange took place and, on the night of 21th day (even at cost of turning tank in a mess, by removing quite a large part of the aquascaping) I netted “that” fish! Since I was definitely interested in getting some of those fry, once I netted the male, I held him in a (wet) hand and forced the “spitting” by means of a toothpick. I got 12 youngsters. I vented him to ensure he was the male, and he soon re-entered the main tank. The newcomers were hosted in a floating nest in the main tank, and were fed, at first, with brine shrimps naupliae (Artemia) then with tiny flakes/pellets. Their growth rate was slow, but, luckily, with there were no troubles. Further spawnings then took place in the main tank, but the results were largely unsucessful. I never stripped the father again, hoping for a more “natural” reproduction, but regrettably, I got no result at all. Maybe in a tank with more hiding spots ...
Grazing on the rocks
Relying on this experience (and a previous one with Spathodus erithrodon), I can say the Eretmodines are interesting fish for a Tang cichlid lover because of their nice shape, interesting feeding habits and absolutely cool temper (toward other tankmates). Their extremely high rate of aggressivity to conspecifics must be kept in mind when aquascaping the tank and, most important of all, when buying fish: either get a “proven” pair (carefully looking at the fishes living at your lfs this should, hopefully, be possible) or otherwise getting at least six juveniles and let them grow.
Mouth brooding female E. cyanostictus
Final remarks (by translator): IMHO these fishes are interesting and above all, were, to me, correctly kept (DO keep in mind the tank size if planning the same experience). Despite this fact, from a theoretical point of view, I do not agree – AT ALL - with “stripping”. Considering all the reported problems with this practice, I feel it should be considered as an exception rather than a rule. Every once in a while (and I repeat ONCE IN A WHILE!) this practice can be considered for hard to breed fishes as the VERY LAST resource.