There is some discussion if the fish from Lompole are hulstaerti or something else. In any case, they are similar in behaviour and spawning.
I bred them first time in 2007 (the "original" type with small side-spot) when they appeared in Denmark again after a very long abscense and have been breeding them regularly since then. I had a short break after losing my original fish to an exeptionally warm summer and later I purchased some "Lompole"-fish. They display a larger, elongated spot on the side conpared to "real" hulstaerti wich have a rounded spot. Males have nice yellow and black fins while the females doesn't.
Barbus hulstaerti "Lompole" displaying the typical elongated spot. Males left and middle, female to the right.
Actually it is quite easy to breed them if you can obtain the fish. For a small fish they are relatively expensive, so you might have to go to a specialist shop to find them or have the local shop order them from a wholesaler if no breeders are found near you.
I use a 16 litre tank for a small group of 4-10 specimens. As you can see in the videos, even in a 16 litre tank they don't take up much space.
For conditioning I seperate males and females and feed them newly hatched Artemia, bananaworms, various granules, flaks, tabs and whatever the other fish in the tank is having.
The spawning tank is prepared with rainwater straight from the barrel in the garden and some peat moss that is allowed to settle on the tank bottom. A clump of moss (javamoss or any other moss) added along with some leaves. Oak, beech, cattappa, it doesn't really matter.
The tank. As you can see, the fish (left side) are very small.
Temperature around 19-20C.
The fish are added and left in the tank for 4-5 days and then removed.
If all works out, you will see the males shake around the females, trying to get them to spawn.
While they are in the setup, I only feed small amounts of live food. I find that live foods seem to affect the waterquality less than prepared foods. Some people leave the fish in with the fry. They don't seem to eat the fry, but I find it easier to be in control without the adults in there.
A few photos from the tank:
Notice the pink belly on the female; eggs ready to get out!
In the beginning, the fry are hanging in the glass, leaves etc. before moving around. They are difficult to spot, but you can see one on the left side of the leaf:
After some days, if you are lucky (with these it is easy to be lucky) you see tiny spotted splinters moving through the tank:
For feeding these small fry I use JBL Nobilfluid and bananaworms. I haven't found Paramecium etc. necessary for these fry.
After a week or so I slowly introduce newly hatched Artemia. If you see the fry eating, they are turned onto a diet of Artemia, bananaworms and eggyolk and other powdered foods. If not, I wait a few days and try again.
JBL Nobilfluid and bananaworms.
Already from the fry are free-swimming I start making daily waterchanges with tapwater. Only one or two cups a day and after a couple of weeks they are able to be in pure tapwater.
Some people have a lot of problems with sex ratios, but I get roughly 50/50 by this method.
Two years ago I tried keeping the species outside in a barrel for the summer, but I lost all the fish. I think it might be because I put the barrel in direct sunlight. I think the water simply got too warm. This year I will try in a spot with shadow from overhanging trees, It should definately be possible.