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13 Great Fish Disease Prevention Tips

Prevention is always better than cure, in this piece we give 13 simple tips to assist in the prevention of disease in your fish tanks

Ensure good water quality at all times through regular water testing

High levels of ammonia, nitrites, and nitrates will all cause health problems for your fish, and will weaken fish allowing diseases to take hold. The only way to check if these polluntants are being kept in check is to test your water on a regular basis.

Ensure water parameters are suitable for the fish you intend to keep

Some fish prefer to be kept within a certain temperature, pH or hardness range. If they are kept outside of this range they may become weak and susceptible to health problems.

Keep only compatible species together

Incompatible fish may fight, harass, or bully one another. Alternatively, active and boisterous fish may disturb slower, more delicate species. Incompatible mixes will stress your fish, which is a prime cause for health problems. Always research your fish before purchasing and use the sites community creator to help avoid incompatible mixes.

Make sure the decor is suited to the type of fish you intend to keep

Fish need to be kept in an environment which is suitable for their needs, this may mean they need planted areas, open spaces, caves, bogwood, fast or slow flowing water or a combination of conditions. For some species, if they are not given the correct environment, they may become reclusive, stressed, and prone to health problems.

Avoid sharp substrates and rocks

Many fish are scavengers, including but not limited to many bottom dwelling catfish and loaches. Sharp stones, gravel or objects can damage these fishes mouth parts, leaving open wounds for infection and disease to set in. If you are keeping any fish that are likely to dig or scavenge, make sure your substrate (gravel) is rounded, small and has no sharp edges.

Avoid sudden changes in light levels, vibrations, or any external stress factors

Sudden changes from light to total darkness will disorientate and shock your fish so make sure room lights are on when the tank light gets switched on or off. Continual vibrations such as those from television or stereo speakers can stress fish if speakers are too close to the tank. Sudden vibrations, such as doors slamming or tapping on the glass can cause severe shockwaves to pass through the tank, which your fish will pick up with their well-developed sensory systems.

Perform regular tank maintenance including gravel siphoning and small water changes

Regular but minor maintenance is better than occasional big maintenance. Gravel cleaning, light filter washing (in tank water), and small water changes on a weekly basis will keep organic load down, which helps to reduce harmful bacteria, and will also help to keep nitrates low.

Provide a varied diet with frequent small feeds (for smaller fish) and do not overfeed

Fish need a variety of nutrients and minerals to remain healthy, and feeding different foods also generates interest, keeping your fish active and lively. Overfeeding however, is a primary cause of bad water conditions and ill health, so make sure you are feeding the right amounts.

Use a chemical filtration medium such as carbon

Over time, pollutants, many of which cannot be easily tested for, will build up in the aquarium and can cause a gradual drop in your fishes health. Chemical filter medias like carbon will help to remove these chemicals. Chemical filtration mediums can be used continually if they are changed every few months, or they can be used in larger quantities for shorter periods (e.g. a for week every two months) Remember that chemical medias can also remove some treatments and plant foods, which is why some fish keepers prefer to use them occasionally rather than continually.

Only purchase your livestock from a trusted retailer

Even the best retailers experience regular health problems with their fish, this is an unavoidable effect of the stress of transport and housing in sales tanks. A good retailer however, will have less health problems and will remove any ill fish from sale until they are fully recovered. Using a reliable, trusted retailer will help reduce the chances of purchasing ill fish.

Avoid genetically weak species such as heavily bred colour types

Some species, which have been over-bred for colour types and as a result of heavy demand, will become genetically weak. These fish may not have a natural immunity to many disease-causing pathogens, and can very quickly become affected by disease. Typical candidates for this problem are Guppies and some colour types of Dwarf Gourami

Keep a mild general treatment available for immediate use for emergencies

Treatments are usually harmful to fish as well as to the disease being treated, which is why they are not used as a preventative. However, there are now a number of mild, wide-ranging treatments available on the market, most of these are based on natural ingredients rather than strong chemicals. In the event of health problems, the immediate application of a mild, natural treatment can help boost the effectiveness of your fishes immune system and prevent secondary infections until a stronger treatment can be obtained, if required.

Monitor your fish

The only way you will know if your fish are having health problems is to observe them on a daily basis for any unusual changes in behaviour or obvious symptoms of disease.

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