How to care for your fish

At Molesey Vets we’re more than happy to see your fish at our veterinary surgery. We provide a variety of fish veterinary services including, consultations and health checks, as well as advice on husbandry and quarantining. A fish Vet from our experienced team can help you with any questions regarding all aspects of caring for your fish. This includes the diagnosis and treatment of any problems.

We provide care & advice for tropical aquarium fish and pond fish. Read about the types of consultations we can offer your fish.

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We always recommend bringing your fish in for regular health checks in order to identify and treat conditions early.

Your vet will need to examine both your fish AND the water in the aquarium/pond.

It is important that your fish is brought in a suitable container with an adequate volume of water. As a general rule of thumb, approximately 1 Litre of water per cm length of fish. You also need to address aeration; this can be provided by a powerhead/airstone and (dependent on the species) temperature control.

We would recommend bringing in extra tank water so they can be transported home in a clean water source.

Please bring in one or more of the diseased population of the tank. If any of your fish have died within the last 24 hours, please keep them refrigerated in water (do not freeze) and bring them in too. Your vet will be able to gather more information by performing a post mortem which may well yield information that could save the remaining individuals.

Please bring a separate 500ml sample of the current tank water. If you have the ability to measure tank water temperature and oxygen saturation at home this will help the vet tremendously.

We will use the sample you provide to analyse water quality by testing for ammonia, nitrite and pH levels.

We have facilities to measure oxygen saturation and temperature but these values change very rapidly and may not be representative of conditions at home.

Your vet will ask you a series of questions related to your fish, including:

  • How long has the tank held fish?
  • What species of fish are kept in the same tank?
  • Are all the fish affected or just one?
  • Are the fish displaying abnormal behaviour (rubbing on objects, staying near the aerator)
  • How often are the fish fed, what food?
  • How often is the water changed?
  • What type and size of filter is used?
  • Are any additives used in the water?
  • Have any treatments been used to date?

We will examine the fish looking for colour changes, behaviour changes, and other signs of sickness. Further testing may be required including taking tissue samples or using x-ray or ultrasound imaging.

In some cases sedation is required to facilitate these diagnostic tests and your fish may need to stay in the hospital for the day.

Fish as a species have a wide range of dietary requirements. Some species can be herbivorous (plant eating), carnivorous (meat eating), insectivorous (insect eating) or omnivorous (will eat plants, meat and insect matter). This means it’s very important to know the species of your fish.

Most freshwater aquarium fish stock a wide range of high quality flakes or pellets. Take note of whether your fish species is surface or bottom feeding (flakes float!). Dry foods DO expire. Try and use them up within 3 months of purchase otherwise their nutritional quality deteriorates fairly rapidly.

You can supplement their dry foods with other food items such as live or frozen products (for example brine shrimp, microworms, water fleas and krill).

You can feed carnivorous fish live food but the food source can often transmit diseases. Frozen items are safer but are often loose their nutritional levels due to the freezing process. Some diseases can also survive the freezing process.

Avoid overfeeding as uneaten food material can severely affect water quality extremely quickly. The frequency of feeding depends on the species of fish you have. Both herbivorous fish and those that are growing need regular feeding. At each feed, only offer amounts that can be consumed within a 15-20 minute period. Remove any uneaten food material using a fine net.  As a rough guide 1-2 times per day with 1 day per week of no feeding is a good rule of thumb.

Husbandry care for fish is basically the aquarium set-up and includes:

  • Tank/aquarium. Most tanks and aquariums are made of glass. The largest tank you can accommodate and afford is the best option to provide a high quality of life. Larger tanks are also easier to clean due to the high volume of water they hold.
  • Substrate. This is the material at the bottom of the tank (e.g. gravel, sand and coral). Chose the material carefully, as there are some that leach substances into the water, affecting water quality parameters such as pH.
  • Filters. These can be small hanging types, under gravel or external canister filters. Filters help to oxygenate the water through circulation, whilst removing nitrogenous waste products via the bacteria that live in the filter. The filter needs to be rated for the tank size you have.
  • Aerators. One example of an aerator would be an air-stone. These help to increase water circulation and thus oxygen levels.
  • Live plants. Live plants help to oxygenate the water, and provide a safe hiding place for your fish.
  • Decorations. These help to make your tank look nice, and also provide another safe hiding place for the fish. They should be approved as aquarium safe.
  • Heaters. These are usually submerged and run on a thermostat helping you to provide the optimum water temperatures.

Quarantine is usually the best time for the vet to examine your new pet fish.

If you already own fish, then it is a good idea to keep your new purchases in an already established quarantine tank. This allows you to monitor them for signs of sickness and disease, thus minimizing the chances of spreading any disease to your existing population.

A quarantine tank will have a similar set up to your normal – it should be large, fitted with an appropriately sized filter and with appropriate heating. We usually recommend not using substrate as this makes the tank easier to monitor and keep clean. Sand and gravel are the perfect place for diseases and bacteria to collect, so are best avoided.

We usually recommend a 2-week quarantine period, after which the new fish can be carefully introduced to the existing population.

Please contact your vet to discuss specific quarantine procedures.

If you would like more advice on caring for fish, contact our friendly team who will be happy to help.


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