I kept Neolamprologus Crassus a number of years ago and while talking to a friend of mine he told me it was one of the few fish he didn’t breed and asked me to write an article about them. I got the original fish from him and he had given me what he thought were a pair of Neolamprologus Crassus and he was right as usual.
Neolamprologus Crassus is a lyre-tailed Tanganyikan cichlid and is from the same family as the Neolamprologus brichardi, but they don’t get as big or aggressive. The males have longer finnage than females and the females tend to be somewhat smaller. Neolamprologus Crassus looks similar to Neolamprologus Gracilis but the main feature that sets the species apart from each other is that Neolamprologus Crassus is much stockier and lacks the filamentous fins of Neolamprologus Gracilis.
When I got the fish first they were about 4cm long so I kept them in a mixed fry tank with Malawi’s and other Tanganyikan’s. It was a very graceful looking fish with a beautiful light blue highlight along the dorsal fin. These fish are found in the Bay of Luhanga, Zaire [Democratic Republic of Congo], West Coast of Lake Tanganyika.
I fed most of my fish mainly on live brine shrimp and Spirulina flake and I also gave them some of my home made Tropheus mix and this was supplemented by a good quality tropical food. Regular water changes about 10% to 25% normally once a week and sometimes more often depending on the rest of the tanks.
I had a spread sheet done up and I would know exactly when I did water changes or when I would see mothers mouth brooding allowing me to move them, this allowed the maximum amount of survivors. I also recorded when the cave spanners’ would disappear and become more aggressive. Guppy’s are a great fish to keep with this type of fish as they are not seen as a treat and they encourage fry and shy fish up to eat as they are always first up to feed.
My hard water really suited the Crassus and it wasn’t long before I decided to split them from the mixed fry tank and put them in a tank of their own as they had started to pair off and were keeping the other fish in the tank pinned into a corner. I had decided on which tank I was going to use 30cm (High) X 60cm (Long) X 45cm (Deep). The tank had a sand base a small amount of bog wood and I built a slate cave just about big enough for them to squeeze into, I also put in some broken pieces of a clay flower pot and an almost complete pot which was about 100mm (4ins.) on top and about 50mm (2ins.) on the bottom as this gave them a place to hide and bring up the fry in private.
As stated above they had started pairing off a few weeks previous so I put them in a quiet corner of the fish-house about chest high which allowed me check on them from the other end of the fish-house hiding behind some tanks. They could go about their business unaware of my presence as every time you approached the tank they would hide, eventually the male coming out and occasionally the female. Every now and then the male would attack me at the glass, which must have been times when some of the eggs had just hatched.
Sometimes before the spawning you would see them digging in the sand, if they did spawn, about four to five days later the fry hatched and the parents would guard the wrigglers, it was hard to count the exact number of fry in a spawn, when they became free swimming you would find it very hard to see them against the sand and that’s when they did venture out. You would only really start to notice them when big brother brought them for a walk/swim. At this stage the fry you could see would be looking after the next generation and so on. You would have your little hierocracy all with their little job to do, if this was a Malawi tank they would be food for their older sibling.
The water conditions as far as I can remember was something like this………
The water chemistry of Lake Tanganyika is very (Alkaline) with a pH value between 8.6 to 9.4 with an average temperature of about 25 °C.
Lake Tanganyika is the second deepest lake in the world, Lake Baikal in Siberia is the deepest. Just a bit of trivia for anybody interested, enjoy your fish keeping........Tom.