Cardinal shrimp (Caridina dennerli) | Care & info

Most shrimp keepers know them but few have actually tried to keep them: Sulawesi shrimp, like the bright red Caridina dennerli (also known as the cardinal shrimp). They have a reputation for being difficult and can definitely be a challenge, but their color and fascinating characteristics make them more than worth the extra effort.

Keep reading for everything you need to know about cardinal shrimp and keeping this uncommon species in your own aquarium!

Cardinal shrimp requirements

If you're looking for an easy species to start with, Sulawesi shrimp most likely aren't for you. Although cardinal shrimp are among the easiest of the Sulawesi species, they're still only suitable for experienced shrimp keepers. If you're new to the hobby, why not consider something a little easier?

Cardinal shrimp can be kept in aquariums of at least 5 gallons, although it's probably a good idea to go for something larger to make sure your water values stay stable. Equipment-wise, you'll need a filter, heater and possibly an extra air pump to make sure the water is well-oxygenated.

Most Sulawesi shrimp keepers prefer to set up their aquariums in a way that mimics the lakes these shrimp naturally occur in. For Caridina dennerli, that means a dark, carbonate-rich substrate, rocks, driftwood and possibly a few plants. A porous rock type that has plenty of surface area for algae to grow on works best.

Because this species can be quite shy, it might be a good idea to not overdo the decorations and go for relatively weak light.

Water quality

Keep in mind that cardinal shrimp might be a bit more fragile than you're used to. They also need higher temperatures and different water values (most notably a higher pH). Reports on the water values in Lake Matano vary, but if your tap water values aren't too extreme, it will probably work. If not, you'll have to consider using reverse osmosis water for your cardinal shrimp tank.

As with all aquarium inhabitants, never introduce Caridina dennerli into an uncycled aquarium. They are very sensitive to bad water quality and the presence of ammonia and nitrites, so keep a close eye on things using a liquid water testing kit. Keep nitrates low by doing careful regular water changes. Don't change too much water at once and add the new water in slowly to prevent shocking your cardinals!

pH: 7.5-8.5

Temperature: 77-86 °F

Tankmates

Because cardinal shrimp are among the more expensive and fragile species, it's a good idea to avoid fish tankmates entirely. After all, you wouldn't want to lose precious fry to a hungry tankmate!

Because many Sulawesi shrimp tanks are set up as biotopes, the most popular tankmates for cardinal shrimp are various species of Sulawesi snails from the genus Tylomelania. The chocolate rabbit snail is a good example. You can also mix multiple species of Sulawesi shrimp in the same tank, as they aren't known to interbreed and most prefer similar water values.

Cardinal shrimp diet

Their diet is one of the more difficult aspects of cardinal shrimp care. These shrimp are naturally detritus feeders that don't always respond as strongly to commercial foods as other shrimp species. The key to getting these Sulawesi shrimp to eat seems to be to feed very fine or powdered foods. Recommendations vary from spirulina powder to micro-organism based foods like Shirakura Chi Ebi.

It's a good idea to avoid "over-cleaning" your Caridina dennerli tank. Although uneaten foods should be removed as much as possible to prevent water quality issues, you should try to leave algae in some places so the shrimp can graze whenever they want.

Breeding cardinal shrimp

Cardinal shrimp are probably the easiest Sulawesi shrimp to breed and you should usually be able to successfully raise the young. Pregnant females will carry around 15 red eggs between their swimmerets (back legs). If all goes well, these will hatch into tiny copies of the adult shrimp after around 20 days. Make sure there's plenty of food available for the fry.

Buying cardinal shrimp

Cardinal shrimp are the most common Sulawesi shrimp in the hobby, but that doesn't mean you'll find them easily. Some specialized aquarium stores might carry these shrimp or be able to order a few for you, but in most cases, you'll have to search for them online.