Coldwater Fish
The name goldfish is misleading as not all fish of that breed are gold in colour. Some goldfish have patches of black or silver. Despite common depiction of goldfish swimming in bowls, they should not be kept in such cramped containers. The limited space gives stress to your goldfish and eventually stunts their growth. A tank provides wider surface area for the goldfish to come up to the water surface to breathe.
To prevent predators fishing into your pond, protect with a secure net. Maintain the cleanliness using a filtration system.
Size does matter. As the size of your tank matters, you need to buy a tank that your fish can grow into. For every inch of goldfish length, you need 30 square inches of surface area to keep your fish happy. It is a common practice to transfer fish longer than 5 inches to a pond. Goldfish thrive in clean environments. Change the aquarium's water once fortnightly. Before you substitute the new water, let it sit overnight for the chlorine to evaporate or use a product that removes chlorine from the water such as Aquasafe.
Goldfish are omnivores. They feed on vegetables and meat. You can buy scientifically prepared flaked food for goldfish. Supplement this with steamed vegetables and frozen live foods. The vegetables are partially cooked to soften them. Frozen meat foods are used to avoid the risk of disease from livestock. Meat is extra protein for your fish and can be given sparingly, like once weekly.
Frequency of feeding is preferred over 1 large meal daily. Breaking up into 3 smaller feedings is good for your goldfish. Goldfish are grazers and scavengers and will always be looking for food although they do not need it. Don't overfeed your fish as they will excrete toxic wastes and ammonia, which poisons the water.
Other health hazards are poor fish diet, sudden temperature changes, bacteria and parasitic illnesses. Signs of sick fish include gasping for air at the waterline, unhealthy or unusual appearances, odd behaviours, swimming at odd angles and loss of appetite.
Common illnesses are swim bladder disorder (SBD), white spots and Dropsy. In the case of SBD, the fish can be seen swimming oddly. You can try self-treatment by fasting your fish for 3 days, followed by a diet of steamed skinless peas for the next 3 days. After this, soak your dried fish food in some aquarium water before feeding them to your goldfish. Keep the water shallow and add salt to make it easier on your fish to swim. White spots remedies are readily available at the shop. Most, if not all, ailments can be treated with off the shelf medications.
The welfare of sterlets in ponds. Sterlets have been available in the aquatics trade for some years now, and are very popular due to their strange, prehistoric appearance. However, because they have a biology that is very different from the other carp-like fishes we keep in ponds, there have been certain issues in caring for them.
For example, they require large, well-oxygenated ponds, and cannot tolerate the presence of blanket weed.
They are also more sensitive to water quality problems. Because of this, some pond owners have struggled to keep them successfully.
Following a dedicated research program conducted by Tetra's R&D department, it is now clear that not only do sterlets have special environmental needs, but also very different nutritional requirements. In fact, much of the reasons for the difficult in caring for them have probably been down to them receiving the wrong nutrition.
Nutritional requirements. A study of existing sinking diets on the market, which are formulated for all bottom feeders (including tench and catfish), showed that they can result in the deterioration of the internal organs. This will then make the fish more vulnerable to stress and disease. Because of the uniqueness of sterlet and sturgeon biology, it is impossible to have a diet suited to their needs as well as tench and catfish.
Sterlets are related to the Sturgeon and there are several species available in the trade, most of which will quickly grow to over a metre (39”) in length. They need a deep, spacious pond with cool, very well-oxygenated water. They thrive in very large, well-filtered Koi ponds, but don’t do as well in the average garden pond.
They may become entangled in blanket weed and aquatic plants. Dealers require a special license in order to sell these fishes, and a good shop will warn you of their potential size and requirements before you purchase them. Do not use potassium based medicants.
Tench
If you were to put a tench in your pond, the only time you would be likely to see it again would be if you were to clean the pond out. Fortunately, golden tench (their colour is very similar to Orfe) are available as a visible, yet functional fish, inhabiting the depths of a pond and taking care of any food that may reach them at the bottom.
Usually available in the golden variety, orfe can make a very lively addition to a pond. Taking residence in the upper layers of a pond, the Orfe is a sleekly built shoaling fish and is capable of jumping clear of the water. Orfe prefer cleaner water than the goldfish, but adapt well to a garden pond with lots of surface area. They are also likely to be the first of the pond fish to show a change in behaviour should water conditions start to deteriorate.
Bred for their 'weird and wonderful' features, fancy goldfish are not compatible as a pond fish with other goldfish. They will rarely over winter on account of their inbred nature and in summer, these slower swimming fish will find it difficult to compete for food during the activities of feeding time.
Similar nature to the traditional goldfish (after all, they are the same species). No need to worry about the compatibility with goldfish. If your pond is suitable for goldfish, these will make worthy companions.
Although still a member of the carp family, the Koi is more of a voracious feeder, keener to scavenge and root around than a goldfish. Plants are a 'no no' as koi will help themselves to planted baskets and do their very best to scatter the aquatic soil all over the pond. (After tasting it of course!). Koi also have a greater growth potential, rapidly outstripping the goldfish clan. The odd small koi can make a useful addition to a pond, and you are likely to be faced with a problem when it gets so big. Koi are best kept in a deeper, unplanted pond compared with a traditional garden pond. Also, watch out for ghost koi, as they can really grow very quickly, as they are particularly voracious feeders.
