Caring For Your Freshwater Shrimp
v1.0
rev. 12/10/04

 

Perhaps you have freshwater shrimp, or are thinking about purchasing freshwater shrimp, but need to know about their care. Freshwater shrimp are quite undemanding little creatures that have few requirements.

 

Water Conditions

It has been my experience that most freshwater shrimp species prefer water with moderate hardness, and a pH of 6.8 to 8.0. For Asian shrimp species, a lower pH can lead to stress and mortality. Macrobrachium shrimp from Peru and Brasil may be better suited for lower pH waters, but that is speculation on my part..

Tankmates

Mixing shrimp and fish can be, at best, a difficult proposition. Many fishes will eat smaller shrimp, and even lager shrimp species may be forced into hiding. Your best bet here is to mix smaller shrimp species in with smaller, non-aggressive fishes such as the Least Livebearer (Heterandra formosa), African flame barb (Barbus jae), small tetras, and the like. Larger shrimp, such as Amano (Caridina japonica) and the smaller Macrobrachium species (such as the Vietnam blue) can be mixed in with larger fish such as swordtails, platys and the like. Larger Macrobrachium species, like the red-spotted and red-claw, are best kept in a tank of their own as they can capture and eat small to medium-sized fishes (at worse) or mutilate fish (at best; see http://www.frankmgreco.com//fishmutilationbyshrimp.pdf). Fishes to avoid would include non-dwarf barbs, cichlids (even dwarf ones), and other large species. However, when it comes right down to it, shrimp are best off kept in their own tank.

Mixing Shrimp

Mixing shrimp species, like mixing fishes and shrimp, can be a difficult proposition. Generally speaking, smaller species can be mixed with smaller species without too much worry about predation. The main problem here is the possibility of cross-breeding. Shrimp taxonomy is not well defined, and shrimp that may not look the same may be the same species. For example, the cherry red shrimp and Taiwan pale blue shrimp are the same species (Neocaridina denticulata sinensis var. red and Neocaridina denticulata sinensis, respectively), and will interbreed. Bee shrimp and Crystal Red shrimp are also the same species (Neocardina serrata and Neocardina serrata var. crystal red), and will interbreed. I don't know if different species will interbreed, but that is a possibility.
When it comes to the long-arm species, there is a definite possibility of shrimp predation. Long-arm shrimp (Macrobrachium spp.) may eat smaller shrimp species and conspecifics.

Aquascaping

As mentioned above, shrimp are really at their best when kept in a species tank. Such a tank need not be large, and anything from a 2.5 gallon on up will house dwarf shrimp comfortably. Larger shrimp species, of course, will require larger quarters. Even Eclipse™ systems will work well*.  No matter what size tank you choose, the basic set-up is the same. I prefer to use a fine sand as a substrate, although it is not essential as long a larger pebbled gravel is avoided. Lots of driftwood and rockwork is also appreciated as are live plants, especially Java moss.

Feeding

The type of food your freshwater shrimp will need depends upon the species. While it's safe to say that these animals are omnivvorous, there are some special requirements. Shrimp of the Caridina/Neocaridina group should have a diet high in greens (algae, frozen kale or collard greens, Spirulina tablets, etc), as should Halocaridina rubra. The pearl shrimp (Macrobrachium luzifugum), being a substrate dweller, should be fed more of a meat-based diet (tablet foods are good for this), although flake food is also readily taken. Larger Macrobrachium species will feed upon frozen foods such as mysis or bloodworms (as will the afore-mentioned shrimp). They may also catch and eat smaller fish. Atya shrimp are generally filter feeders, and should be fed small particles suspended in the water. Crushed flake, Cyclop-Eeze™ and enriched Artemia nauplii are readily taken. But when it comes right down to it, experiment. Try different types of foods. The better the variety, the healthier the shrimp.

Breeding

If you are looking for some easy to breed shrimp species, the Neocaridina group is for you. All produce fully formed young that are miniature versions of the adults. Macrobrachium luzifugum also falls into this category, as do the Chocolate shrimp (Macrobrachium sp.), red-spotted shrimp (Macrobrachium sp.) and yellow-banded shrimp (Macrobrachium sp.). For other Macrobrachium species, Atya gabonensis, and the Amano shrimp (Caridina japonica), brackish water is required for larval development, making these shrimp more difficult to rear than other species.

Feeding Larval Shrimp

 If you want to take a shot at raising shrimp with small larvae, you will need to raise food for them. As for culture systems, there are two basic approaches you can take. The first approach is single batch culture which actually works pretty well for small spawns as soon as you identify the first larval food source. The second approach, recirculating bath, works well for larger spawns over longer larval cycles where repetitive water changes become somewhat impractical. For the single batch culture, you can use one gallon glass tea jars partially immersed in heated water inside a twenty gallon-long aquarium. Five jars per 20-long if memory serves me correctly. Each jar can be a separate spawn or a separate feeding regime until you work out the nutritional needs for your desired species. To start off, place the larvae into enough water so that their concentration is 50 to 100
larvae/liter of water in the tea jars (you can go above 100 later if things work well). Place a submersible heater in the water (approx. 5 inches) in the 20
gallon tank. Set the temperature to your best guess as to the required temperature for your species. This method calls for 50-75% daily water exchanges in each jar so pre-heated conditioned water needs to be on hand daily as well as appropriate larval feeds (i.e., phytoplankton, Artemia, Daphnia, and rotifers). For longer larval development periods or when excessive water loss would occur from daily changes (more a problem for marine and brackish tanks) use the recirculating method. You can use a 5 gallon bucket for the culture vessel. Place a bulkhead fitting at the base of the bucket and a standpipe with a series of fitted nitex screen sleeves (80 microns, 120 microns, 180 microns, and 300 microns). These are just recommended sizes, they are not carved in stone. Place the bucket above a column of BioBalls, Biospheres, etc... that empty into a large plastic wash-tub (available at K-mart if you hurry before they go out of business). Use a small submersible pump to pump water from the reservoir back up to the culture bucket. The air should be added by a weighted or fitted ring around the inside base of the bucket to allow continual gentle mixing. Above the BioBalls a little floss should be used. Do not use to fine a grade of floss, you do not want to remove most live feeds form the water. Place your heater in the reservoir on bottom. I have used both types of systems successfully with several species. Large commercial marine shrimp hatcheries producing 30 to 50 million post larvae per month actually use a vastly upscale version of the first method.

 

* When using Eclipse™ systems to house shrimp, it is advisable to wrap a piece of nylon window screen around the intake strainer. Failure to do this may result in smaller shrimp (including babies) getting sucked into the filter.

Copyright 2004 by Frank M. Greco/Frank's Aquarium