The benefits of feeding live food to fish in a community tank are many: live food will improve vigor and color, and more closely resemble the food found in the fish’s natural habitat. Live food is easily obtained.
Some drawbacks include the transmission of diseases or parasites to the aquarium, it is time consuming to maintain the cultures, and a lot of space needs to be devoted to raising live foods. The cost of equipment and supplies needed to maintain cultures is also a consideration for the beginner.
In this article I will discuss how to raise Daphnia. This article will be part of an on-going series on live foods. You can find many more related articles on http://www.kingdiscus.com.
Daphnia belong to a group known as the Daphniidae, and are close relatives of the freshwater shrimp, and the brine shrimp (Artemia). Their generic name is generally referred to as “water flea.” This common name is derived from the jerky movements of Daphnia in the water. The over 150 different species can be found in North America, with a similar amount of species growing in Europe. Some of these species find common ground on both continents.
Daphnia are a small crustacean, and are great to use as a fresh food because they will exist in the tank water until eaten by the fish. Daphnia can also be sterilized if it is felt necessary by placing in a 5% solution of Clorox for 3 to 5 minutes. Very few micro-organisms can survive this. Be sure, however, to rinse them thoroughly before feeding!
Daphnia can be raised both indoors and outside. Many people raise daphnia in a small children’s wading pool. A more controlled environment, however, is done indoors, and can be done year round if one lives in northern climes. This can be as simple as a couple of two liter bottles, to a 20 gallon tub purchased from a store such as Menard’s. The ideal situation is to have as much oxygenated surface area as possible, so if there is room for a larger container, by all means use it. A shallower environment suits daphnia best for prolific growth.
Setting up the environment for daphnia is quite simple. Many methods are used for collecting the water to use for the culture. The best advice I have heard is from Joe F. of Circle City Aquarium Club in Indianapolis, IN. He gave a presentation at the August meeting of Southwestern Michigan Aquarium Society, and recommends using tank water saved from a tank change. Joe has been raising live foods for a long time, and has had good success. His video presentation was top notch.
PH levels for successful Daphnia cultures should be in the range of 6-8, and should be more alkaline than acidic. If raised outdoors, no aeration is needed. If raised indoors, aeration should be adjusted to produce large bubbles. Small bubbles in the daphnia culture will cause the bubbles to become lodged in the carapace of the culture, and they will die.
Water temperatures for Daphnia magna are not a high requirement, but the optimal temperature should be in the 64-72 degree range. they are very tolerant to changes in temperature, and can withstand fluctuations down to freezing. In fact, Daphnia can be frozen and kept in the freezer, and then revived when needed. Moina withstand a higher fluctuation in temperature than do D. magna.
Lighting should be in the neighborhood of eight or more hours light per day and light intensity equal to or greater than 850 lux. A simple light and a timer can accomplish this indoors.
Feeding the Daphnia is where most aquarists fail. Daphnia feed on dissolved organic matter, yeast, various groups of bacteria, microalgae, and detritus, or mulm. Organic fertilizers, such as fresh cow manure. It is not recommended by our breeder, though, because of the antibiotics and supplements fed to dairy and beef cattle. A much better mixture is a combination of one tablespoon each of spirulina, soy flour, and active dry yeast, added to a pint of water. This mixture should be added so that the water is cloudy, but you are able to see the bottom clearly, and observe the Daphnia swimming in the culture. This mixture should be added carefully every two or three days, being careful not to over feed. At this time, you should see an abundance of Daphnia, and they can be harvested to feed your fish.
Harvesting is quite simple – simply use a small aquarium net, observing that the smaller Daphnia fall through the netting to grow further. In this way, the adults are harvested, and can be fed to your fish. The younger Daphnia can go on to produce still more fish food. Harvested Daphnia can be kept in the refrigerator for several days in clean water.
Daphnia are high in protein, and a very good diet for tropical fish. Some aquarists feed them exclusively. They provide up to 70% protein to your tropical fish, and are an excellent source of live food for the aquarium.
Much can be written on the culturing of Daphnia. this guide is only meant to help the beginner to live foods to establish a colony, and feed live food high in protein to their fish. A series of article on live foods is forthcoming, and can be viewed at http://www.kingdiscus.com.
About The Author
Alden Smith is a published author who has been publishing on the internet for 7 years. Visit his website, http://www.kindiscus.com, for articles, software, and other resources. This article is one of a series available at http://www.kingdiscus.com.
Written By: Alden Smith
Most of our marine fishes come from the wild. It isn’t unusual for the fish to be carrying a worm infection in its intestinal track. It’s been estimated that up to 30% of fish in the wild have some kind of intestinal worm infection. This number can considerably increase as fish are kept in holding tanks along transfer points, where they can share diseases and infections.
In the wild, this isn’t much of an issue. The fish can find enough food for its own needs and the needs of the worms. The worms, of course, are taking nutrients away from the fish. But if the intake of nutrients is enough, the fish & the worms are happy. However, I, the aquarist, am not happy. I want worms out.
If the fishes are de-wormed (which is very easy to do) the aquarist doesn’t have to worry about the worms taking nutrients away from their fishes.
Unfortunately, it isn’t easy to always tell if a fish has these worms. The symptoms of a worm infestation match other intestinal disorders. Generally though, the symptoms and observations of fishes with intestinal worms include:
Strange faeces (stringy, solid lengths, colored wrong, worms in faeces, etc.)
Fish eats voraciously but doesn’t seem to gain weight
Fish eats but is losing weight, or seems to be wasting away
Fish eats but is losing coloration and clear marking boundaries
Fish eating habits have changed to picking at food or it stops eating
Obviously the above set of symptoms can apply to certain other conditions, however, the ‘strange faeces’ is the one symptom you’ll come to rely upon most.
You have to be a Super Pooper Snooper to ‘sniff out’ the problem.
I’d like to cover in this article the three most common problems which are indicated by the above symptoms. Peculiar faeces are usually a sign of an intestinal/internal problem.
There are three basic possibilities when it comes to an intestinal problem.
This reference outlines the three nicely:
http://www.petsforum.com/personal/tr…nfections.html
Garlic is not a remedy. It has been suspected of helping in one case of internal parasites. The fish was fed solid chunks of it. Garlic juice does nothing in this case. I can elaborate on this if you want or you can read a thread on that: Garlic
Knowing how long you’ve had this fish would help in the diagnosis, as well as whether or not you use a quarantine system to verify the fish was healthy before you put it into your display tank. Since I don’t know this information when I wrote this article, I have to assume either possibility and provide how to deal with each.
Whatever the intestinal problem, the fish needs the best water quality, the best diet AND supplements added to its diet. Remember, it’s eating for two or two thousand!
For diet and supplement help, check this out:
Feeding Marine Fish and Fish Nutrition
If the fish isn’t eating then the only way to get medication to the intestinal track is to put the fish in a quarantine tank and treat the water with chemicals that will kill the internal condition. The drug Praziquantel (a.k.a. Droncit) will treat intestinal worms, Maracyn Two for Saltwater fish will treat an internal bacterial infection and Metronizazole will treat dinoflagellate infections.
To be conservative: I recommend two ways forward:
1. If you’ve had your fish for several months or more: First check your source water for contaminants. Use only the best source water and make up a new batch of salt water. Now check that freshly made up water for quality/contaminants. If it passes, then adjust it for pH, temperature and salinity, mix some more, then do an 80% water change and see if the fish seems to ‘perk up’ (e.g., starts eating or eats more or swims around more in the open). If the fish definitely perks up then it maybe a combo of water conditions and bacteria. In this case, I’d treat the fish for an internal bacterial infection. Move fish to a hospital/quarantine tank and treat with Maracyn Two for Saltwater fishes. Begin with a double dose and continue double dosing what is recommended on the medicine insert. With proper nutrition and water quality, the fish may gain control and conquer the internal infection.
2. If you recently acquired the fish: Treat the fish for worms (using Praziquantel) first and if no improvement, treat for dinoflagellates (using a medication containing Metronizazole). You can use a medication that includes both these (see below).
If the fish was fat and eating properly and being fed a proper diet (see above reference), with vitamin and fat supplements, it can live without eating for several weeks, providing all other environmental and water quality conditions are as they should be and the fish isn’t diseased. Praziquantel is best administered orally so if your fish isn’t eating, try to get the fish eating.
De-worm all newly acquired fishes with Praziquantel right after acclimation. Acclimation suggestion: It Was Acclimation, I know. . .
Dose Praziquantel as instructed below. Wait 5 days and dose again.
This treatment is over!
Medications:
Maracyn Two for Saltwater fishes. Made by Mardel. Contains the antibiotic Minocycline with B complex vitamins (to stimulate appetite). Available at some local fish stores, Petco, and on line.
Praziquantel. Praziquantel may be hard to find. But it is available on-line along with other medications at: National Fish Pharmaceuticals, FISH DISEASE . . It is also available on-line from PondRX PondRX – Do you feel the need for speed? – Home. . Unfortunately, the quantity of Praziquantel you need to order as a minimum order may be more than you’ll need in the next few years. It is administered at 23mg per pound of fish, in their normal food.
There is a commercially prepared anti-parasitic pellet food available. It is made by Jungle. The active ingredients in this food are levamisole (a stimulant for the fish immune system), Metronizazole, and Praziquantel. This particular formula will kill a much broader spectrum of intestinal organisms. Also, the product Gel-Tek Ultra Cure PX can be used instead of Praziquantel. The aquarist is looking for a treatment that the fish will swallow (not a water treatment). For both of these products, just follow directions on the medication.
Alternative Meds (overseas). I try to be on the look-out for meds available outside North America. I’ve recently come across some that are suitable for de-worming. Those in the UK and Europe may find Fenbendazole or Piperazine more readily available. They are dosed at 250mg/100g of food, fed for 7 to 10 days. Medications and medications containing these will likely come with dosing instructions. Always follow label instructions.
Metronizazole. Also found in several products. (See above). Follow the directions that come with the medication.
BE THE SUPER POOPER SNOOPER. Watch your fishes’ faeces! (This is a hobby?)
This article may be used freely as long as this resource box, with intact hyperlinks, is included.
Lee Birch is the author of this article, originally posted here, used with permission by Chris Merriman
To Learn How To Obtain, Sustain & Maintain Your Aquatic Mini-World, visit LearnAboutAquariums.com
