That Fish Blog – Aquarium Advice and Information

Patty here.

It’s inevitable. Just when you think your pond is looking its best and all is right with the world, they invade. Aphids, weevils, moths, beetles and others descend onto those beautiful lilies, floaters, and marginals like a summertime scourge.

So what are some solutions to these nasty little pests? Being that your pond is most likely home to other inhabitants like koi, goldfish, frogs and other desirables, you’ll have to consider safe treatments, and the factor will rule out most chemical solutions.

Aphids are one of the most common invaders, sucking the life out of lilies, water lettuce and other soft-leaved aquatic plants. To avoid or minimize their foothold, prevention is the first step. Remove yellowing or damaged leaves from plants, they serve as beacons for the little suckers to home in on. Resist the urge to blast them off of leaves with a hose, as it usually serves more as high speed transport to other plants than as an eradication method. If only a few are present, you may be able to dunk the leaves or pull out putted plants and spray them away from the pond, at least as a temporary fix.
For more serious infestations there are some other methods to consider. You can try natural predator introduction. Ladybugs and green lacewings are natural aphid predators and though you may have a couple of these arrive on their own, you can purchase them online or at many garden centers and introduce them to feast on your pests. Orfes, minnows and guppies may also eat those that you can rinse into the pond. There are increasingly available herbal sprays for pond plants that will not harm fish, but be sure to read labels carefully. These sprays are usually formulated with herbal extracts, so they’re natural and mild, but sometimes too mild to really handle the situation. If you have the means you may even be able to formulate a similar spray by making a strong tea of rosemary, garlic, thyme, chrysanthemum or mint. Some suggest adding a cup of vegetable oil or a dash of dish soap to the mixture as well, but especially in the case of the soap, be sure to spray and rinse the plants well outside of the pond.

Other common pests include mosquitos, Leaf miners, and aquatic moth larvae. Prevention of infestation of these pests consists mainly of good maintenance of the pond and surrounding area, good water movement and the absence of dead leaves and debris in and around the pond. The natural predators mentioned above as well as others like predator wasps and dragonflies that are drawn to flowering plants and water may help, as may the small insect-eating fish mentioned above. Mosquito dunks are effective for the control of many waterborne insects, but they will also affect beneficial water insect larvae, so if you like those dragonflies, they may not be the best option. They are safe for use with fish.
Even though these pests can create a real headache for those of us with a love for aquatic plants, the overall aesthetic and health of a well- planted pond is worth the hassle. If you have any questions about a pest plaguing your water feature or you have a remedy that has worked for you to share, please let us know!

Image referenced from MorgueFile here.

Hello, Frank Indiviglio here.

Anchor worms are crustaceans (specifically copepods) and as such are more closely related to shrimp than to worms.  They often make their presence known in outdoor ponds as winter turns to spring.  Lernaea elegans, the most commonly encountered species, remains dormant during the winter and becomes active as the water reaches 55 F or so. 

Identification

Anchor worms bury below their host’s scales, but betray their presence by trailing ¼ to ½ inch-long portions of their black, thread-like bodies from infected fishes.  They usually attach about a fish’s gills, eyes or fins, but can occur most anywhere.  Other signs include inflamed or raised scales and efforts by fishes to dislodge the parasites (leaping, rubbing).

Infestations most commonly occur during the spring, when the parasites are searching for new hosts after their winter dormancy.  Conveniently for the anchor worms, the immune systems of pond fishes are at their weakest at this time, having been stressed by cool temperatures and the long winter fast. 

Secondary Bacterial Infections

Anchor worms rarely cause fatalities, but the wounds they inflict frequently become infected by opportunistic Pseudomonas and Aeromonas bacteria.  Ever present in the pond, these pathogens can easily kill fishes, especially those with depressed immune systems.

Avoiding Anchor Worms

Be especially careful to check for anchor worms when purchasing koi or goldfishes in the late winter or spring…those that have been wintered outdoors may be infected.  They also parasitize weather fishes, channel catfishes, hi-fin loaches and other species commonly kept in outdoor ponds.

Anchor worms of various species can also be introduced to your collection via tropical fishes which have been raised outdoors.

Treating Parasitized Fishes

Fortunately, Jungle Lab’s Anchors Away is an effective treatment for infestations of anchor worms and certain other parasites.  Be aware that this medication will kill crayfishes, snails and other invertebrates, and that carbon should be removed from your filter while treatment is ongoing.

It is also useful to add an ultraviolet sterilizer to your pond’s filtration system.  UV sterilizers will kill anchor worms in the free swimming larval stage (they are not effective against adults), thereby preventing re-infestation.

Further Reading

A detailed article (Food and Agriculture Association of the United Nations) on the life cycle of anchor worms and related parasitic copepods is posted at.

Please write in with your questions and comments.  Thanks, until next time, Frank Indiviglio.

Image referenced from Wikipedia and originally posted by Brian Gratwicke

Patty here. Just about anyone with an ornamental pond has either heard of water hyacinth or has a personal experience with hyacinth to share.  I find it to be an interesting and useful plant, and here in PA we don’t have to worry about its invasive tendencies and notorious reputation like those of you in warmer climates.  I thought I’d give a little background on this floater to help you get to know it better.

Water Hyacinth (Eichhornia crassipes) is native to tropical South America where it forms vast mats on the water’s surface.  It is sun and heat loving and can reproduce at a ridiculous rate by producing long runners and stolons, which is why it is cosidered a noxious and invasive species in many states and countries.  They can double in population within about two weeks if the conditions are right!

It has unique structure.  Each leaf has a spongy bulb which allows it to float on the surface, and the leaves have a waxy, waterproof feel.  The root system hangs in a long-stranded cluster beneath each plant, and the roots are white to dark purple-brown and very hairy.  These plants also produce beautiful flowers in the peak of summer, a cluster of light purple flowers with six petals each and a violet and yellow accent on the top petal of each flower.

Hyacinth does have its notorious side, and the reputation is well-deserved.  However, in cooler climates, and with responsible management this plant has carved out a valuable niche.  Because hyacinth grows and reproduces so rapidly, it makes a terrific solution to provide shade on ornamental ponds.  Two to three single plants is usually way more than enough to cover a broad area of water surface within a few short weeks, ad it will be necessary to prune the mat to keep the population in check.  The floating mat is a refuge for pond fish and frogs, a food source, and a form of natural, efficient biological filtration. 

The foliage and blossoms are as pretty as they are useful, but the roots are the real prize.  Not only do they provide a surface for fish to deposit eggs, but they serve as a safe haven for fry, tadpoles, and other organisms as they grow.   They have the ability to remove toxins, excess nutrients, and other compounds from the water and have even been used in industrial water treatment applications.  Hyacinth helps to oxygenate, and can even be placed in the filter’s sump as long as there is enough sun!

Hyacinth can be purchased for use in garden ponds in most aquatic garden and pond centers.  We sell it out of our retail location, but do not ship it. It is actually prohibited in many southern states.  If you choose to introduce hyacinth to your pond, don’t overdo it, purchase 2-3 plants, and see how they grow!  Provide them with plenty of sun, and protect the plants from your fish (who will think they are delicious) until they start to reproduce.  And as always, be careful and responsible if you need to dispose of extra hyacinth to ensure that they don’t find their way into natural ponds and waterways.

Anyone who keeps a koi pond in cooler temperatures has been there. You start getting a few warmer days in late March and your koi, who had been inactive all winter, begin to swim around and look for food. Being the “good” koi keeper you are, and just an all around nice person, you start feeding your hungry friends almost immediately. The feeding continues to increase, while your pond continues to get greener. Meanwhile the local garden store is getting in a load of excellent looking Asagi or Shiro Utsuri Koi direct from Japan next week, and though you already have a questionable number of little Koi in your 1000 gallon pond, one more couldn’t hurt, right?

Pond keepers are creatures of extremes and it’s nothing we’re ready to apologize for (I mean, koi are soooo cool!). But, from a biological balance perspective, it’s really easy to start tipping the scale in your pond in favor of algae and unfavorable health conditions, particularly in the cooler weather.  

Believe it or not, koi in an outdoor pond do not have to be fed to survive. Being the scavengers that they are, they’ll have no trouble finding the nutrients they need among the detritus, bugs, and general wild things that end up in your pond throughout the season. What this means to you is everything you add to the pond, whether it be more fish, fish food or plants, adds to the nutrient load. In early spring, this nutrient load is particularly important for several reasons. First, your beneficial bacteria are not yet running full steam. This means ammonia takes that much longer to break down. When you combine that with the fact that your fish, and their immune systems, are still in slow motion due to the cooler water temperatures, a high nutrient load can cause problems. In addition, the natural “nutrient sucker-uppers,” your aquatic plants, are also struggling to gain a hold for the new season, so that part of your natural filtration is crippled as well.

Many koi keepers than ask, how can I get around this problem? I love my pond and I’m not going to stop feeding my koi, and I’ll probably add more fish to the nutrient load from time to time because they’re too awesome to pass up. Our response to you: avoid the extremes. Be sure to have the necessary test kits on hand to make sure levels remain nominal throughout the season. If you start to see problems, just like in an aquarium, try a water change, or add some bottled bacteria to help the chemistry settle. If your pond starts to get cloudy or full of algae, try adding more plants, or cutting back a few feedings. If you’ve tried all of these solutions and the problems are not going away, it may be time to consider a larger filter system or (gasp!) trimming your koi stock a little.

Good luck with your pond this season!

Patty here. Koi  are basically colored Carp.  They are descendants of Asian and Central European Carp originally domesticated and used as food in China and Southeast Asia.  Their hardy nature and adaptability made them easy to propagate and transport to new locations.  Beginning over a thousand years ago, Asian breeders were selectively breeding these fish to develop natural color mutations into the brilliant and brightly colored fish that exist today. By the early 19th century through the early 20th century, desirable color patterns were established by the Japanese, and Koi started gaining world -wide popularity. 

As Pond season rolls around this year, many might be considering the addition of Koi to a water feature. Here are a few tidbits to think about before you purchase koi.

• Koi should only be housed in ponds at least 1000 gallons or more. The bigger the better. The depth of the pond should be at least 3 feet to help the fish to avoid overexposure to sun and heat and to allow them to survive harsh winter temps. If your pond does not fit these criteria, goldfish and comets will be a better fit for you.
• The bright colors shown by koi make them beacons for predators. Herons, raccoons, bears, and even cats and dogs amongst others may find koi a fancy meal if they can reach the fish. Proper depths and shade trees can help the fish to stay safe.
• Koi have big appetites. They are omnivores, and will enjoy a varied diet of staple pellets along with frequent treats of fruits and veggies like watermelon, peas, lettuce, and corn. Koi will also eat plants at the surface of the water and will happily dig at the roots of potted plants on the pond too. You may need to cage the plants to preserve them, or at least top the soil with river rocks.
• By encouraging these fish to the surface for feeding, they can become quite tame, often hand feeding. This behavior allows for visual health inspections that may need to be treated.
• Koi should not be fed if the temperature of the pond sees a constant of 50 degrees or lower as they cannot properly digest proteins.
• Along with their big appetites comes a lot of waste. Be sure to provide ample filtration and aeration particularly if you have a number of these fish in a minimally sized pond.
• If provided with a proper environment, koi can live for decades, and have even been reported as living more than 200 years!
• Wild carp can grow to almost 6 feet in length, and ornamental koi are known to reach lengths of about 3 feet in length. Carefully consider this in relation to the pond you plan on housing the fish in as they grow QUICKLY! Juvenile fish can double in size in a year, and though the growth rate can slow after 2 or 3 years, the fish continue to grow for 10 to 15 years. They’ll need plenty of space to grow and live comfortably.
• Koi spawn in the spring. Females grow bloated with eggs and males compete for the opportunity to fertilize the eggs when she releases them. You may see one fish being chased aggressively around the pond by several others. The female is the target of the attention. Supply breeding mats, floating plants, or plants at the bottom of the pond as a place where she can release her eggs. You may be lucky enough to see new additions to your population not long after, though survivability is usually not high unless the fry are collected and nurtured.

Koi can be the pride of a backyard pond, but they do require a bit more attention and a lot more space than goldfish and comets.  When you’re ready to add fish, give us a call or shoot us an e-mail with any concerns or questions so we can help you to have a successful pond experience.  Be sure to save the date for or annual Pond Festival, too, May 16-17 2009!

Image referenced from Wikipedia and originally posted by Stan Shebs