This article is about a favourite Tanganyikan Shell-Dwelling species of mine, Neolamprologus multifasciatus. I refer to them as "multi's". For those of you that do not know this fish it is often referred to as the "smallest cichlid". They reach a size of around 1.75 2 inches for the males and the females are around one inch.
The reason for this article is to try and explain some behaviour I observed which others might find interesting.
First some background info on my tank setup: I have 13 multi's in a small breeding tank measuring 30 inch long X 14 inch high X 14 inch wide. I use a UGF with 3 inches of medium sized gravel, a fluval #1, and a whisper H.O.T type filter. The gender mix is 7 males and 6 females. They are fed twice daily on frozen blood worms and frozen newly hatched brine shrimp.
These fish are referred to by Ad Konings in Tanganyikan Secrets as a colony guarder, meaning the fish live and breed in a colony, all protecting each other from predators.
My fish spawn regularly and I often have 5 or 6 fry swimming around at any given time. I have been told that the maximum spawn they will have will be 20 fry for a mature breeding pair, but I have yet to see this.
The behaviour I observed in my tank that I am writing about happened over the last two weeks or so when I observed 6 or 7 fry swimming around (and in) one of the shells, being closely guarded by the female (mother) and half-heartedly guarded by the male (father). Observations over the next few days discovered that the largest male of the colony was actually attacking and eating the fry, and he has gradually reduced the school down to 1 lonely & elusive free swimmer. I couldn't believe what I was seeing as this had never happened before in the 12 months or so that I have been keeping multi's. I then went through all my books on the behaviour of these fish (of which information is hard to find), and came up with what I believe to be the answer. In one of the texts a one line comment enlightened me. It was written "although the dominant male sometimes will not tolerate too many fry at once." A light bulb suddenly came on in my head and I spent all my spare time with my head glued to the front of the tank, and sure enough, I discovered that another pair had actually been raising a school of about 12 fry all this time. Now that the other spawn had been reduced to all but one, the aggression basically stopped as sudden as it started. I found this to be amazing as my fish are always well fed (if not over fed), and I made the stupid assumption that if they were well fed the big fish would be less inclined to eat the small fish.
Anyway, I hope this information has been useful for some of you, and I am now wondering if this behaviour is particular to multifasciatus, or is it common with other colony type fish such as tropheus? This and other icthyologist-boggling questions remain unanswered until the next exciting episode of "Tanganyikan Caviar". Stay tuned............ :-)
And.... Some months later....
Tanganyikan Caviar - The long awaited sequel!!
You may remember that a few months ago I wrote an article on the mysteries of cannibalistic Neolamprologus multifasciatus. I am still breeding these little monsters and continually have fry in grow out, just not enough.
In the last article I wrote about the aggression of the dominant male toward extraneous fry, and it appeared as though he was eating fry whenever there was more than one school being reared in the tank at once.
The thing that I have always found difficult about shell dwellers is if you want to save a large number of the fry, you have to remove them from the general population. With any other type of cichlid what most of us do is siphon the fry out, or catch them in a fine mesh net and put them in a grow out tank, net, or floating container. To remove shell dweller fry (my experience is limited to Neolamprologus multifasciatus and n. occellatus) is not always easy; I have had the best success with the occellatus. Every time my hand would go in the tank, the fry would dart into the mother's shell in which they were spawned. This made collection easy by simply placing the shell (including mother and fry) in a container under the water, then removing the container and putting it in the holding tank. Unfortunately, with the multifasciatus, it is a different story. After the fry are a week or so old, they tend to take refuge under the shell rather than in it. This poses a few problems; being when you try to remove the shell, the fry dart under it and not in it. So, if you do remove the shell, you miss half the fry; secondly, you also remove the protective mother (who retreats into the shell), leaving the fry fair game for any other fish.
Keeping in mind that Neolamprologus multifasciatus are a colony guarding fish (supposedly), and fry removal isn't all that necessary, I have thought long and hard on why my N. multifasciatus fry kept on disappearing, and came up with a good theory and a completely different answer!
The theory (which came about between myself and my main man down at the local aquarium) is that when you start a colony of fish in a tank, be it multi's, Tropheus , Princess' or whatever, you expect to lose a few of the slower swimming fry until the "colony" instinct kicks in. This made perfect sense to me, so I was eagerly awaiting the day that my male multi realized what a colony life was all about, and presto, I wouldn't have any more disappearing fry! Wrong again! I was starting to get disheartened, so I decided to split my multi's up into pairs, as I had heard from some fellow fish roomers that this was a good way to keep them and they could be quite productive in this set up. So it was time to strip down my 30" tank and grab the multi's in lots of 2 and 3. After doing this, I drained the tank down, scooped up all the gravel, lifted the UGF plates, and right before my eyes was around 20 free swimmers, ranging from half an inch, right down to 3/8." I was cackling like a mad man as I netted them and put them in a holding tank. Well, as you can see, this solved my problem of collecting the fry, and I was pleased with myself for finally finding a good use for the UGF (I was going to throw it out).
I have now set up 1 male and 4 females in a 10G (I swapped the non-producers for something else at the aquarium) with a light layer of gravel, shells, and a small box filter in the corner, and they are breeding like rabbits. I no longer have the problem of fry disappearing, as the male is a good protector, and I didn't put the UGF in there, so I can now quite easily net the fry out if I need to.
I hope you enjoyed this article, and I will continue to document my blundering breeding program as I strive to have every fish tank in my fish room filled with free swimmers.
© Copyright 1996 Peter Hill, all rights reserved
Hill, Peter. (septembre 24, 1996). "Neolamprologus multifasciatus (Boulenger 1906)". Cichlid Room Companion. Consulté le mars 08, 2021, de: https://cichlidae.com/article.php?id=30&lang=fr.