Fish

The best tropical fish for novice aquarium hobbyists are hardy and adaptable to captive environments. They also tend to be small and non-aggressive, with few special care requirements outside a mature, well-maintained aquarium of suitable size and setup. In this guide, we explore 10 of the most beginner-friendly tropical fish species.

Feeding Daphnia It should come as no great surprise that daphnia are an excellent source of nutrition for small fishes; countless species the world over have heavily relied upon this abundant resource for eons. Fish keepers have been touting the benefits of feeding live daphnia for about as long as people have been keeping fish. The nutritional value of live daphnia depends greatly upon what it eats. Direct enrichment of daphnia is easy and effective. Choose a smaller alga with a well-rounded fatty acid profile. Tetraselmis green alga and Spirulina alga are excellent choices of feed and can be found in aquatic supply stores, along with other algae options. One may supplement B-vitamins with the use of active baker’s yeast, though only very sparingly due to its ability to quickly foul the culture water. Daphnia are typically about 50 percent protein by dry weight, and moina even a bit more, making them especially useful for growing out juvenile fish. The use of an automatic feeder is best, though daily manual feeding will suffice. Store-bought frozen algal pastes are a nutritious and cost-effective source of food. Enough food should be added to produce a green tint to the water (approximately 105 to 106 cells/ml). Culture water should not be allowed to clear for long, if at all; at the same time, one must always be careful to avoid overfeeding. ,Harvesting Daphnia to Feed to Fish Only one of the two vessels are harvested at a time. Using a rotating schedule, one vessel can be harvested every one or two days. Harvest is best undertaken a few hours after re-greening the culture water, as to allow for maximal enrichment of the daphnia. To collect the animals, it is best to use an appropriately sized (something on the order of 50- to 150-µm) plankton screen. A short length of tubing can be used to direct the water through the drain to the screen, which should sit in some water to avoid leaving small air bubbles on the animal. The harvested batch can be temporarily transferred to a bottle before being fed out to the fish, but should be used as soon as possible. Harvests will generally alternate between the two vessels; however, always harvest and restart any culture that appears to be declining. Take care to avoid feeding spoiled food; all thawed, unused portions of algal paste must be refrigerated and used within a few days or discarded.,By Kenneth Wingerter Properly caring for even a small, simple aquarium system can be fairly time consuming, leaving many aquarists eager to cut a corner or two to save a little time. One common way that fish keepers accomplish this is by using prepared, store-bought foods. To be sure, the measured use of certain high quality prepared foods is usually acceptable. The inclusion of some whole frozen items is markedly better. And a highly varied combination of prepared and frozen foods is better yet. But whatever the feeding regimen, the use of live foods has been proven time and again to greatly enhance the immunity, digestion, growth, coloration, and general health of captive species. Further, it offers the opportunity to observe the natural feeding response of one’s aquatic animals. Certain small cladoceran crustaceans, such as Daphnia and Moina, not only serve as highly nutritious live food items, but are quite easy to culture in perpetuity. Meet the Cladocerans: Daphnia and Moira Daphnia spp. and Moina spp. are closely related and belong to the animalia order Cladocera. (Editor’s note: For the sake of brevity, the author is using the species name Daphnia throughout most of this article to refer to both daphnia and moira.) The cladocerans are a group of small, primitive, and mainly freshwater planktonic filter-feeding crustacea. They have a carapace that covers the entire body except the head. Their flattened, leaflike legs (or phyllopodia) are used for suspension feeding as well as for respiration. Cladocera are commonly referred to as water fleas due to the hopping motion they make when moving about in the water. Daphnia are distributed throughout much of the world, though they are less abundant in the tropics where water bodies are usually nutrient poor (only six of the 50 daphnia species occur in the tropics). They prefer warm, still, or slow-moving waters with heavy organic loads. These may be ephemeral bodies of water, like rock pools, where conditions only sporadically allow for growth and reproduction. 

 Anchor Worm Infection In Fish There are many skin parasites that infect fishes. One such parasite is the anchor worm. However, despite its name, it is not a worm, but a large, parasitic crustacean of the Lernaea species. And although the parasite can infect any fish, pond fishes are most susceptible. Once attached to the fish’s skin, it buries its head deep into the muscle tissue. Symptoms and Types A fish infected with anchor worms will have red and inflamed skin irritations. Take a closer look, and you can see the parasite’s body sticking out, appearing like whitish-green threads. The fish will also rub or brush itself against objects, in an attempt to get rid of the anchor worm(s).

Before starting your multi-fish tank, make sure you have what your aquarium will need to properly maintain it. “When planning a new tank, consider compatibility among tank mates, the species that will inhabit this mini-ecosystem,” says Jessica Allen, DVM, CertAqV, who works with aquarium enthusiasts in Florida, Georgia, and Tennessee. “Beyond tank parameters and cycling, a happy and thriving population must coexist in a low-stress, low-competition environment.”  For beginner aquarists, start with a 10- to 20-gallon tank, like the Tetra Complete Tropical Fish Aquarium Kit. Tank size will affect what fish may be kept. ,When housing fish in your aquarium, it’s important to ensure the health and safety of all the fish in the tank. Community fish should be able to live peacefully together and have similar needs, making them easy to care for. 

The Nitrosomonas bacterium feed on ammonia and converts it into nitrite (NO2). Nitrite is slightly less harmful to fish than ammonia, but it is still not good to have around. Nitrites make it more difficult for fish to take up oxygen (O2). Thankfully, there is another bacterium that helps with this stage of the cycle. The Nitrobacter bacterium feeds on the nitrites in the water and converts them into nitrate (NO3). Fish can tolerate high levels of nitrate much better than high levels of ammonia and nitrite. Plants are very helpful in the nitrate phase of the nitrogen cycle because they feed on nitrates. Once a system has a sufficient number of the aforementioned bacteria to fully process the ammonia and nitrites, the system is considered to be “cycled.” This brings us back to pH. If the pH drops below 6 in a given system, the Nitrosomonas bacterium will not adequately process the ammonia in the water. If the pH eventually gets low enough, the nitrogen cycle will cease to function all together. If the pH levels rise above 9, as mentioned earlier, very high concentrations of toxic ammonia (NH3) are present. The nitrogen cycle itself tends to reduce the pH of a system. Most freshwater fish would fall into a pH range between 5.5 and 7.2, with a few exceptions at both the high and the low end. It is not just fish that need to have an appropriate pH to thrive. Live plants do best in a pH range between 6.5 and 7.5. Beneficial bacteria prefer a slightly higher range, from 7.0 to 8.0. In general, a good pH range that would satisfy most fish, along with live plants and bacteria would be 7.0 to 7.2. It is important to note that pH in the aquarium is not completely stable, with small fluctuations occurring throughout the day and night. Many things can affect the stability of the pH within a system. Aeration, gravel, fish tank decorations, temperature, and nitrate levels are just some of these.,What Is pH?

Digestive Disorders Most digestive disorders in fishes are caused by parasite infections. However, not all parasites cause problems for fishes — some live in a symbiotic relationship with the fishes. Symptoms and Types The symptoms can vary depending on the parasite causing the digestive disorders, but usually include weight loss, lethargy and loss of appetite. Young fishes are especially susceptible to digestive disorders and can die before any symptoms arise. Such parasites which cause these type digestive disorders include:   Protozoan parasites (e.g., Spiionucleus, Hexamit, and Cryptobia) Worm parasites (e.g., tapeworms) Protozoan parasites Spiionucleus and Hexamita infect the intestines of cichlids, bettas, gouramis, and other aquarium fishes. Apart from the symptoms listed above, fishes with these two parasites produce stool that is white and stringy. Cryptobia, another protozoan parasite, infects the stomach of African cichlids.

Pleistophora Hyphessobryconis & Broken Back Much like other animals, fishes can have bone and muscle disorders. Symptoms and Types  One such bone and muscle disorder is Broken Back Disease, which is typically due to a vitamin C deficiency. This disease will literally bend the fish’s backbone. However, injuries are sometimes the cause of an abnormal backbone. Another typical bone and muscle disorder is caused by the parasite Pleistophora hyphessobryconis. This parasite attacks the skeletal muscle – responsible for movement – of freshwater aquarium fishes, like neon tetra and angelfish. The fishes infected with the parasite, which has caused muscle damage, will then have abnormal muscle movements. To identify the parasite infection, the veterinarian will perform a microscopic examination. However, there is no treatment for this particular bone and muscle disorder. The only way to prevent the disease from spreading is to remove all infected fishes from the tank, aquarium or fishpond.

If you’re thinking about adding goldfish to a home aquarium or pond, you may be wondering—how long do goldfish live?  A goldfish’s lifespan can reach 30 years, but only if they’re properly cared for. Learn how to give your goldfish the best shot at living a long life. 

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A half-acre pond would be equivalent to a circular pond about 170 feet in diameter or, in a more natural shape, about 220 feet long by 100 feet wide. There are several options for constructing a new pond without a liner or cement shell. The easiest is to excavate the pond into the local water table and use the ground water. However, for this to work well you must live in an area with a fairly stable high water table. When ground water is within a few feet of the ground surface, gradients into the pond from the edge can be shallow. But if ground water is 10 feet below the surface, the pond will look more like a quarry, with dangerously steep sides. Even if the groundwater is near the surface this approach may still be inappropriate. Ground water elevations tend to fluctuate significantly during the course of a year. This fluctuation may be several feet or several dozen feet, with high water levels in spring, fall, and winter, but very low levels in the summer. The result is that the excavated pond would go dry for several weeks (or months) of the year. Fish would not enjoy this. There are natural wetland features that provide precisely this type of habitat: prairie potholes and vernal pools. Across the Midwest these ephemeral ponds offer invaluable habitat for migrating waterfowl and indigenous animals. These ecologically significant wetlands are disappearing rapidly, so a project that would create a constructed prairie pothole would offer a great service. However, keep in mind that these temporary ponds do not harbor fish, so your plans for koi would be out, as would floating-leaf aquatic plants. Instead, your planting scheme would have to be built around local emergent vegetation. If you want a permanent pond, there are really three basic options: 1) excavation into local impermeable soils–with compacting, 2) clay liners or 3) bentonite or chemical additives. Soil conditions vary substantially around the country. In some areas the soil has a heavy clay component. At minimum clay should comprise at least 10 percent of the soil mixture–substantially higher percentages are desirable. I strongly suggest having a professional soil analysis done. If the soil proves satisfactory, the next step is to remove all vegetation from the area and dig the pond. I recommend that pond depth be kept to less than 10 feet in order to minimize the chances of seepage. More than 10 feet of static head pressure can push water through the pond floor and walls. When planning the excavation, add about 30 inches to the depth to compensate for the planting soil added later. This material will also protect the pond against cracking that might result from freezing and thawing. The soil that will become the pond floor and walls should be turned to a depth of at least 12 inches and all rocks, stones, roots and so on removed. Then this soil is compacted to a depth of about 8 inches. The impermeability of the compacted soil will be destroyed if you plant it. Aquatic plant roots, which can reach 2 feet into the soil, will create channels for water to seep out. Therefore, you will want to add at least 30 inches of a loam and clay planting soil when the pond sculpting is completed. If your local soils do not have a good clay base, you can follow the ancient Chinese pond building technique of adding a clay layer. A 12-inch clay layer (coarse soil with at least 20 percent clay content) is spread over the pond floor and walls. Keep in mind that the excavation depth should be the sum of the desired pond depth, plus 12 inches for the clay, plus 30 inches for the planting soil. The ground should be prepared as described above for compacting, and the clay should be applied in 6-inch layers, compacting the first before applying the second. Finally, add the 30-inch planting soil layer. The third alternative is to use a soil additive, such as bentonite, to create an impermeable layer. Bentonite is a clay colloid that expands to 10 times or more its volume when wet. This expansion seals pores in the soil. Whether or not your soils can be sealed this way depends on a number of characteristics that can only be determined by professional soil analysis. In appropriate soils 10 to 30 pounds of bentonite are applied per square yard of surface area. The additive is mixed with the soil (after it is prepared by removing all debris, stones, etc.), then compacted. Adding the planting soil is the last step for filling the pond. Pond liners are available for ponds the size you are considering. Permalon (Reef Industries, Houston, TX), for example, can be placed and sealed to cover your half-acre area. A 6-inch gravel base and then planting soil can be laid over it. The company claims that heavy equipment can be used on top of their liners to move gravel and soil without damage. Posted by: Chewy Editorial Featured Image: via Lisa Ewing/Shutterstock,Q.