Fish - the extra dimension to a pond By Andy McConnachie from Aqua Landscape Design

Fish can bring a pond to life and will control insects and other pond pests, however there are a few golden rules to remember before they make it into your pond

Introducing fish into your garden pond can create a whole new dimension, whether it’s a shoal of native Rudd in a wildlife pond or a few high grade, Japanese koi. Fish not only bring a pond to life but are useful in controlling insects and other pond pests, however there are a few golden rules to remember before any introduction. Making sure that your pond is right for the species of fish you wish to purchase, planning their arrival and knowing how to care for them is paramount. A little bit a research can mean avoiding problems like having to re-home fish that have become too large, losing fish to an unsuitable environment or having specimen plants destroyed by certain species.

New ponds need to be acclimatised to having fish. Firstly, fish should not be introduced until the pond has been filled for a week and plants added. Introduce hardy species, such as goldfish, first.

These tend to be better at coping with fluctuating water conditions which are often symptomatic of new ponds. Only add a few fish at a time, this stops the naturally present filter bacteria being overwhelmed by a sudden influx of waste to process.

When choosing fish, go to a reputable aquatic centre and look for active fish that are interacting with their surroundings and tank mates. All the fins should be complete and held out from the body, they should look well fed and the scales should appear smooth and glossy.

It is advisable to buy all of your fish from the same source, as this reduces the chance of pathogens being introduced to your existing stock it also means you can retrace any problems with the fish.

After buying your fish you should always go straight back home and start acclimatising them to your pond. Being left in a bag for long periods of time is not only stressful for the fish but the limited amount of water creates a detrimental environment as fish are very sensitive to changes in temperature and water chemistry. Once home, open the bag, folding the top down so the bag floats on the pond, scoop some pond water in and leave for 10 minutes. Add another scoop of pond water and leave for a further 10 minutes. Check the water inside the bag and outside to feel for any temperature difference (a thermometer is also useful if you have one). If no temperature difference is detected then slowly release the fish into the pond. The best time to introduce new fish is during spring and autumn, when the temperatures are low and oxygen levels high.

Gold Fish, Shubunkin and Sarasa Commets

Minimum pond size: 450l with an area 90cm deep
Max fish size: can get up to 20cm or more but tend to grow to the size the environment will support
Filtration and oxygen levels: can thrive in ponds with or without filtration
Feeding: can survive without supplementary feeding but do better if fed flake and pellet food.

Green and Gold Tench

Mini pond size: 1800l with an area 90cm deep
Max fish size: up to 25cm
Filtration and oxygen level: can thrive in ponds with or without filtration
Feeding: bottom feeders should not need additional feeding

Golden Rudd

Mini pond size: 900l with an area 90cm deep
Max fish size: up to 20cm
Filtration and oxygen level: can thrive in ponds with or without filtration
Feeding: should not need additional feeding

Gudgeon

Mini pond size: 450l with and area of 90cm deep
Max fish size: up to 15cm
Filtration and oxygen level: need good levels of oxygen and water movement
Feeding: should not need additional feeding

Gold and Blue Orfe

Mini pond size: 2700l with an area 90cm deep
Max fish size: up to 35cm
Filtration and oxygen level: need high levels of oxygen and good filtration.
Feeding: feed with floating sticks and pellets.

Koi Carp and Butterfly Koi Carp

Mini pond size: 4500l with an area at least 90cm deep
Max fish size: up to 90cm
Filtration and oxygen level: need high levels of oxygen and very good filtration.
Feeding: feed with floating sticks and pellets. Will eat pond plants.