Maidenhead Aquatics Topical Tips - May 2011

With Easter and the many bank holidays behind us its time to enjoy the sunshine and perhaps hope for overnight rain…

Outdoors

With temperatures nice and high this early in the year the pond season is off to a great start. Unlike bedding plants, outdoor fish are cushioned against extremes of temperature by their natural environment but to avoid problems I’d advise checking that your pond is over 10 c before adding any new fishes by using a pond thermometer. As with indoor fish, check your water for ammonia and nitrite before adding any new stock. Most people, especially gardeners, are familiar with pH (the measurement of acidity/alkalinity) but this is not a huge issue for pond fish which just hate extremes or rapid fluctuations.

With this in mind, it seems odd to spend ages floating fish in a bag on the surface of the pond when the only thing this equalises is temperature – you can bet that new fish will head straight to the bottom of the pond where things are colder anyway. To avoid a stressful introduction, gently transfer your new pets into a container such as a clean bucket and fill this slowly from the pond using a watering can or perhaps the outlet from a small water feature pump. Don’t rush this process as you only get one chance to do it properly. The longer you take, the easier it will be for the fish so aim for about 15 - 30 minutes and keep an eye on uncovered containers to make sure your fishes don’t jump out. When you’re ready, lower the container into the pond and let the fish swim out in their own time.

It seems obvious but please take your fishes straight home. They won’t appreciate a detour to the shops on a hot day and as the water gets warmer the oxygen levels drop. To give them an upgrade to first class travel, buy a polystyrene box or fish transport bag to place them in for the journey home.

Goldfish and their relatives can make for an interesting mix of colour and form in a well-maintained pond

With so many pond fish to choose from, it can be tricky to know what’s best for your situation. Let’s have a look at some of your options:

Goldfish – Traditionally the pond fish, the good old-fashioned goldfish is hardy, popular and easy to breed. There’s no difference whatsoever between indoor and outdoor goldfish and as long as they are long and streamlined with a single tail, fish from bowls (dirty word that) and aquaria can be added to an outdoor pond where they will thrive and generally enjoy a much longer life. Fancy varieties with exaggerated body shapes such as fantails, moors and ryukins are a poor choice for garden pond life and do better in a large aquarium away from predators and competition. Long-finned goldfish are known as ‘comets’ and are nearly as hardy as their short-finned relatives. All of the goldfish varieties are friendly fish that will readily mix and happily cross, often producing some interesting looking offspring! Occasionally, some breeders will cross fancy goldfish with pond varieties to improve colour and for this reason we’re very careful to source our stock from cold parts of the world were fishes are bred to withstand the rigours of the British winter. All of the goldfish varieties can grow to around a foot (30 cm) in length.

Shubunkin – The name that lots of people struggle with ‘shoe-bun-kins’ or ‘shubs’ for short, are a colour form of goldfish and will happily swim and interbreed with them.

Sarasa Comet – With stunning red and white colouration, sarasas are a good alternative to koi in smaller ponds and are just glamorous goldfish with all the same requirements.

Canary or Lemon Goldfish – Despite the name this recently developed goldfish variety neither sings, nor tastes any different to normal goldfish but is a lovely yellow shade that looks great when mixed with sarasa comets.

Wakin – A double tailed form that shares a sleek body form with a tail more like that of a fancy goldfish but without the tender constitution.

Canary goldfish look great when mixed with shubunkins or sarasa comets

Koi – Although not seen as the status symbols of twenty years ago, koi carp are still great aquatic pets if kept properly and are firmly in the ‘Labrador with fins’ category of aquatic pet. Properly in this case means a large volume of filtered water and a stocking level of around 500 gallons/2,000 litres of water per fish. Being carp, they love to forage through the mud and will stir up any sediment and completely trash any pond plants they encounter. Like any big fish, koi will be a problem if purchased for a small pool with plans of increasing the size as they grow, as in small ponds they are often stunted and misshapen unlike the sleek, beautiful fishes that they can become.

Butterfly Koi – These recently developed fishes are a long-finned form which possesses a sleek, distinctive outline which many find attractive. A bit of a marmite fish which can cause strong feelings from carp purists, butterfly koi definitely appeal to those seeking an elegant fish which is a bit different.

Ghost Koi – Are the result of crossing a single-coloured koi with a wild-type carp and are normally hardier than their posh parent. The ghost part of the name comes from the fact that in a pond the more brightly coloured head and back are the only visible part of these friendly fish. ‘Ghosties’ have all the personality and destructive abilities of koi but are more forgiving of water quality lapses or overcrowding. Despite their durable nature, they are best given the same conditions and allowed to thrive. Like koi, they can quickly grow to over 2 feet/60 cm in length and many fishes are considerably larger.

Golden Orfe – Are really under-rated pond fish but do have a couple of quirks that need to be mentioned. As they are originally a colour form of the European Ide, they are a river fish and demand high oxygen levels. This means that they will suffer in small pools with little water movement and ideally should be kept in situations where large filters or waterfalls mean that they can enjoy swimming in a current. This same high-energy swimming often leads to them jumping out of smaller ponds. A blue form is also seen and adds interest and variety, as well as remaining slightly smaller than the more vigorous gold version.  One massive advantage they have over carp is the fact that they don’t eat plants, making them a far better choice for large, planted pools. Orfe are hardy fish and you don’t often see a sick one – a good job as they’re sensitive to many of the chemicals found in some pond treatments and new tap water. Always check the labels before using any disease treatments and make sure that you use a good dechlorinator when adding tap water to your pond. Orfe are fast growers and can reach 18”/45 cm within a few summers.

Golden Rudd – Are the fish that most people really should keep instead of goldfish. An ornamental form of a native species, they are hardy and prolific to the extent that an established population in a planted pond can provide hours of delight for water gardeners, kingfishers and herons. If you’re looking for a native fish for a large wildlife pond, these are the one to go for and despite their larger size of around 12”/30 cm; are far less destructive to other pond creatures than fishes such as sticklebacks. Occasionally the wild form is seen, traded as ‘red-fin rudd’ and these are a handsome fish that can look great in a clear pond.

Green Tench – Are a fish that really lean on a reputation gained in the early days of water gardening. A dedicated bottom-dweller, this native fish was sold as a combination of pond vacuum and ‘doctor fish’ in the belief that it’s body mucous was helpful in healing wounds of other fish. Nowadays you are more likely to see the golden ornamental form – not least because the olive-green colour of wild-type fish makes them very difficult to spot, even in clear water. Tench will surface from the depths to feed together with other pond fish and add a bit of mystery to the garden pond. Easily sexed by comparing the large, spoon-shaped pelvic fins of males with the smaller counterparts of females, these are great addition to the fish community and the smaller gold form seldom reaches the 24”/60 cm that wild green females can attain.

Sterlet and Sturgeon – Are primitive ‘sharky-looking’ fishes that have little in common with the other carp family species that make up the overwhelming majority of pond fish. These are fishes that tend to pace the pond perimeter and lack the swimming skills needed to avoid thick growths of blanketweed or pond plants, often become fatally entangled. They also love the cold and thrive best in big, deep ponds with good filtration and water movement where they can be fed year-round. Like orfe, certain chemicals can be problematic for these fish and the same precautions apply. Related to some of the biggest freshwater fishes in the world, sterlets are the baby of the bunch and reach around 36”/90 cm with sturgeon capable of doubling this size.

Indoors

After the royal wedding mania that gripped the nation, I thought I’d ease us out gently with a couple of royal fishes. There are a few to choose from and Royal whiptails (Sturisoma), Emperor Tetras (Nematobrycon) and King Tiger Plecs (Hypancistrus) are joined by both King and Queen Angelfish (Holacanthus) not to mention a whole host of others.

I’ve chosen two species that deserve a closer look and they have both earned their place as popular aquarium species.

Our first species is the Princess of Burundi or Fairy Cichlid (Neolamprologus brichardi). Named for their elegant shape and graceful fins, this is a Tanganyikan fish that lives a soap opera existence. Equipped with teeth designed for fighting, they put family first and a pair of fish will establish a territory that soon becomes the heart of an empire. From a cave in the rockwork fry start to emerge and their parents defend their home against all comers. Soon after the first batch, a second brood of babies appears and the first brood starts to help defend the territory and guard their younger brothers and sisters. Eventually a big multi-generational family is claiming all the territory that they can and older fish gradually drift off to start their own empire, or remain part of the home team until space becomes available. All this is amazing to watch and makes for a spectacle unrivalled by any other aquarium fish apart from some close relatives.

Neolamprologus brichardi is a fascinating fish to keep

Our second fish is far more colourful and is a marine fish that has been popular for years. With a dazzling purple and yellow pattern, the Royal Gramma (Gramma loreto) is a fish which doesn’t need much other than its looks to get by. All the more remarkable that this clever little fish has a great character to go with it and rapidly becomes a favourite. Found deep in Caribbean reefs, Grammas can be a little shy of bright lights at first but soon find a home in the rockwork and share their bright colours with the aquarium keeper. When it comes to breeding, males take the lead and will make a nest of algae and court any females in the area before settling down to guard the eggs until they hatch and drift away into the plankton. Unlike some marine fish, this one won’t cost you a fortune or prove tricky to feed or accommodate. Although more of a challenge to rear than clownfish, breeding and rearing baby grammas is not beyond the reach of dedicated hobbyists and this was one of the first marine fish to be successfully bred in captivity in the 1960’s.

With both beauty and brains, the Royal Gramma is a perfect choice for marine aquarists