After more than 30 years of aquarium and breeding experience, which began at the tender age of 12 with discus fish and continued soon with Neocaridina shrimp, my wife and I gave up keeping new forms and colors a few years ago. Since 2016 we have been reflecting on the beauties that nature offers us and from then on we only kept wild shrimp.
Of course there was no way around this beautiful Caridina dennerli. But despite our many years of experience, we hit the wall with the first two attempts. We still knew too little about these animals and their keeping conditions. From 2018 we finally managed to read a lot and learn how to breed the Cardinal shrimp. From that moment on, other species of Sulawesi shrimp were gradually added. Finally, three years ago, we only specialized in Sulawesi shrimps.
The country of Indonesia and the countless islands of the archipelago have fascinated us for at least as long as our aquaristic experience.
Our aquariums
The conversion to Malili and Poso tanks took some time. There are currently 5 standalone Sulawesi aquariums, each with 84 liters (70 x 40 x 30 cm). This tank size seems to be ideal in terms of water volume and floor space. We manage to keep the fluctuations in the water parameters and apparently the germ load low.
All tanks are set up exactly the same.
Each one is filtered with an HMF corner filter. The air lift is operated with an Eheim 400 Air and ensures a flow rate of approx. 300 l/h. A good movement of the relatively large water surface is thus given. The air also keeps the pH value stable at 8.2.
An 11 watt UV-C light is installed in the free space of the filter corners behind the mats, which is switched on twice a day for one hour. This light is to be operated with caution, unfortunately we have already managed to kill shrimp with it :-(. No ray may leave the filter corner and get into the aquarium.
A 75 watt heater keeps the temperature at 29°C.
For the lights, we work with our own LED design, with 15 watts, 6400 Kelvin, 2400 lumens (160 lm/W) with Samsung LEDs.
In addition, there are two Söchting Mini Oxydators in each tank. These are empty after a week at 29°C. We refill them with the weekly water change.
Experimental daylight aquarium
Two of our tanks are a small exception. They are daylight tanks. That means no artificial lighting, just daylight. Describing the processes and the behavior of the animals in these tanks would go beyond the scope here. We would be happy to write another report on this topic.
Hardscape
The aquariums are kept simple. We do not use substrate or wood to reduce germ load and to avoid sources of rot. In order to create many hiding places, many perforated stones or slabs of slate pile up on top of each other.
We experimented with different stones. Even if perforated rock contains lime, it does not change the water values. At pH values around 8.2, no lime dissolves. It would only do that at pH values in the acid spectrum.
However, the white color of the stones reflects so much light that, despite UV and hydrogen peroxide, a constantly growing carpet of algae is encouraged. This is also the basis of food for the shrimp.
Feeding
We feed very varied. In addition to the food basis algae and biofilm on stones, we feed the shrimp every two days in the same order with organic vegetable powder (beetroot, cucumber, spinach), spirulina powder, Sera Vipan food flakes.
We leave the shed exoskeletons in the tank when cleaning.
We adjust the amount of food but not the feeding times for the different populations. Apart from the Blue Leg shrimp (Caridina caerulea), all other species we keep (C. trimaculata, C. dennerli, C. striata, C. marlenae) are nocturnal. When feeding in the morning, we found that the food remains untouched until the evening. It wasn't gone until the next morning. In order to shorten the time the food stays in the tank, we only feed in the evening just before the lights go out.
Water changes
We change at least 20-30% of the water weekly.
We chose the heat method to dissolve the SaltyShrimp 8.5 Sulawesi Mineral salt. We make a kind of broth to add the salt. About every two months we heat a few liters of reverse osmosis water to about 80°C. Then we salt the hot water on the stove heavily. We let it brew for two hours while adding heat and stirring frequently. In the end, the brew looks like milk and has a conductivity of around 6000 μS/cm (3000 ppm).
We always keep 50% of the required osmosis water for water changes ready, to be able to act quickly in an emergency. From Friday noon, 100% will be anyway produced. On Saturday morning, 50% reposed osmosis water from last week and 50% fresh osmosis water are then mixed. The rest of the fresh water is left for next week.
Now we salt the osmosis water with the brew to a conductivity of 100–120 μS/cm (50–60 ppm). Then it is brought up to temperature and a UV-C light is hung in for disinfection.
While the exchange water now "matures", we clean all side glasses. We completely empty two tanks every week. So stones out. Then we vacuum the sludge everywhere as best we can without vacuuming shrimp. Detritus is also extracted from the filters. And then all oxidizers refilled. The tanks are then cleared again.
When the water mixture has then reached its temperature, the conductance has leveled off at approx. 160 μS/cm (80 ppm) due to the subsequent dissolution of the salt and the heating. Now the water is filled in. The filters, UV clarification and heaters remained on during the cleaning.
The slightly milky cloudiness is completely gone the next day. At the end of the week we then have a conductivity of between 200 and 250 μS/cm (100–125 ppm) due to post-hardening and evaporation. In this way there are only very small and slow fluctuations in the conductance, which apparently do not pose a problem for the shrimp, from 160 to 250 μS/cm (80 to 125 ppm).
Siphoning
When cleaning the tank, the newly born shrimp are often smaller than the excrement of the adult animals. So when siphoning, no small net is suitable to protect the young shrimps. Over the years we have developed an ingenious but very simple system which makes it difficult to suck in small animals.
We use the following High-Tech devices for this 😉
- Bucket (10 liters)
- hose (16/22mm)
- cut up drinking bottle
- gravity, small difference in altitude
The hose fits exactly on the drinking opening of the halved bottle, which we use as a suction retarder. The inner diameter of the tube is reduced from 16mm to 4mm through the drinking opening. This slows down the flow. Due to the "bulky" shape of the bottle, the mulm swirls around and has a residence time of about 15 seconds, so it flows off very slowly.
We always change the water in pair. I move the siphon slowly and flat over the glass (no substrate is used) and watch the contents. The small and large shrimp have enough time to flee from the bottle. My wife holds hose and bucket. Due to my wife's sitting position, the difference in height from pool to bucket seems to be perfect. This does not create a strong suction, but it is sufficient to absorb any muck. If we do catch a shrimp, you can see it in the bell for a long time and clearly. My wife then pulls the hose up so the water inside flows back out and gently flushes the shrimp back into the tank. This way we don't have to put a shrimp out of the bucket back into the tank with the net and no shrimp ever leaves the water.
Ok, it's expensive, time-consuming and our Saturdays simply belong to our Sulawesi shrimp.
Husbandry conditions
We are aware that truly species-appropriate conditions for animals are only available in their natural environment. Nevertheless, we try to keep our Sulawesi shrimps as close to nature and healthy as possible.
We still do a lot of aquaristic manual work.
Alex Winterhalder and family
