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Pond Myths Exposed

20 "Old Wives Tales" Debunked Once and For All 
by Aquascape, Inc.

1.  Predators will eat all of your fish!


There is a constant fear in the water gardening community that raccoons and other four-legged predators will go swimming in your pond, and while they’re in there, they’ll help themselves to some of your prize koi, shubunkin, or goldfish.  When you go out to your pond in the morning and discover you’re missing a fish or two, it’s very tempting to blame it on such critters, especially if you didn’t see it happen.  There has to be a reasonable explanation, and predators are as good as any, right?


However, take the following facts into consideration before you jump to any conclusions.  Raccoons generally won’t swim.  That’s not to say they never swim, or couldn’t stand on the side of your pond and take a swipe or two at your fish.  Fortunately, most fish will swim to a deeper, more protected part of the pond when a predator is threatening them. 


The one predator with legitimate credentials is the blue heron.  These tall, long-legged, big-beaked birds can easily wade into your pond, help themselves to any fish they think look tasty, and fly away with their bellies full.  They are a protected species, so they are off-limits if you’re thinking about taking revenge on them.  However, a scarecrow, a motion-sensing sprinkler that can be set up alongside your pond, ready to fire a steady stream of water at a heron, has had some degree of success in warding off these curious critters.  It’s a good idea to move the sprinkler often though, to keep them guessing. 


Giving your fish a place to hide dramatically helps their odds of survival.  Plenty of lily pads give them some protection and will work to minimize attracting a heron in the first place.  Other protection measures include a cave-like structure than can be built in during the pond’s excavation, or if you already have a pond, they can be added with a little pond remodeling. 


Rocks are essential in creating these hiding places in your pond.  Crevices, or miniature caves, can be created within the rock walls of your pond. 


The possibility of pond predators seeking out your pond is, indeed, a valid concern in terms of your pond’s inhabitants, but the possibility shouldn’t be a reason to avoid building a pond.


2.  The presence of rocks and gravel make it difficult to clean your pond. 


You are susceptible to buying into this myth if, and only if, you’ve never experienced pondering with rocks and gravel in your pond.  If you have a smooth-bottom pond, and each season you’re amazed at the amount of much and grime that collects on the bottom, you automatically rule out rocks as a solution.  You keep visualizing that same amount of muck on top of the rocks and gravel and say, “NO!” to even considering them.  It’s understandable.  It seems logical…until you learn the rest of the story. 


Rocks and gravel offer a natural place for aerobic bacteria to colonize and set up housekeeping.  This bacteria breaks down the fish waste and debris that would otherwise accumulate in the pond and turn into sludge.  Regardless of your pond’s location (i.e. close to trees and loads of leaves), or how many fish you have in it, you’ll find that having rocks and gravel in your pond not only makes it look better, but it makes it healthier as well. 


So, contrary to the myth, having rocks and gravel on the bottom of your pond actually allows Mother Nature to clean up after herself, saving you headaches and hours of work trying to keep the bottom of your pond muck-free.


3.  UV lights, such as those in the UltraKlearTM UVC, are the best way to keep your pond water clear.  


UV clarifiers are one of the ways to keeps your pond water clear, but certainly not the only way, and arguably not the natural way.  The fact of the matter is that if you have a pond that’s naturally balanced, in which the aquatic circle of life is rotating the way that Mother Nature intended, you don’t need a UVC at all.  In this naturalistic setting, the fish eat the plants, then produce waste that gets broken down (along with other pond debris) by aerobic bacteria that’s colonized on the rocks and gravel below, and then it’s taken back up as nutrition by the plants, continuing the cycle.  A naturally balanced pond is a low maintenance pond because Mother Nature is doing the maintenance work for you.  Pretty good deal, don’t you think?


There are several drawbacks to the UV solution though.  First, no matter how intense, UV clarifiers don’t affect string algae at all, and so this problem is not addressed.  Secondly, after the regular algae is killed, it generally falls to the bottom of the pond, biodegrades, and provides another wave of nutrition for another (often larger) algae bloom.  If you’re not careful, it’s easy to encourage larger cycles of algae blooms by using a UVC.  If your pond is unbalanced, the choices are minimal.  The third, and most obvious drawback is that a UVC isn’t cheap, and the bulbs usually require replacement every season.

4.  Your pond must be at least three-feet deep in order to keep koi. 


There are thousands of two-foot deep ponds around the country, full of happy and healthy koi.  A common myth is that ponds must be built at least 3-feet deep, especially if they contain koi or are located in a colder climate.  The water in a two-foot deep pond will generally only freeze 8 inches down, even in the coldest of climates, because of the insulating qualities of the earth that surrounds the pond. 


A pond that is too deep could be considered a swimming pool by your local government and therefore fall under strict guidelines and codes.  Also, more digging means more work, more water to fill the pond, and more additives to treat algae and fish illnesses.


5.  Koi can’t be kept in a pond that also contains plants. 


In a naturally balanced ecosystem, koi and plants complement and need one another.  In nature, fish feed on plants.  As a result, the fish produce waste, which is broken down by aerobic bacteria on the bottom of the pond, which, in turn, is used as fertilizer by the plants to grow and produce more natural fish food.  It’s known as the circle of life, and to imply that koi and plants shouldn’t co-exist is to ignore nature. 


On the contrary, fish naturally love to eat plants, and most of the time they’ll (the fish) survive nicely without you feeding them at all due to the plants and algae.  On the other hand, you have to have a sufficient volume of plants to accommodate the koi.  In the naturally balanced pond, proportionality is always a key ingredient to success. 


6.  You have to bring your fish inside for the winter. 


Fish do fine during the coldest of winters as long as you given them two feet of water to swim in, oxygenate the water, and keep a hold in the ice with a bubbler, allowing the naturally produced gases to escape from under the ice.  Otherwise, you let Mother Nature do the rest.  The fish will spend the entire winter hibernating at the bottom of the pond and then they will slowly wake up as the water warms in the spring.


7.  Your pond water must be tested on a daily basis. 


This myth comes from the aquarium industry and it has a lot to do with the fact that an aquarium is a much smaller body of water and the small size makes it more difficult to balance.  Mother Nature never tests her water, and her ecosystem does just fine.  A well-conceived, naturally balanced water garden normally requires very little testing. 


8.  A pond in my backyard means I will have a lot of mosquitoes. 


Mosquitoes will generally only lay their eggs in still, stagnant water.  If the mosquitoes happen to lay eggs in your pond and the mosquito larvae hatch, the fish in your pond will consider them a treat and will pick them off the water’s surface with great enthusiasm.  Your skimmer will sweep up whatever the fish miss.  Another option is to use a natural mosquito larvae killer, such as Mosquito Dunks. 


9.  You cannot have a pond in an area where there are a lot of trees. 


In nature, ponds and trees go together like ham and eggs on a breakfast table.  Yes, you will have more leaves in your pond in the fall, but, by the same token, the shade provided by the tree(s) will help minimize the algae bloom in the summer.  Furthermore, if you have a skimmer sucking the top quarter inch of water off the top of your pond, it will pull most of the leaves and related debris into an awaiting net.  This takes a few minutes to empty, and it can be a daily task in the fall if your pond is close to trees.  Add it all up and it’s a trade-off that most full-sun water gardeners would love to have!  So don’t worry about trees and pond.  They’re fine.


10.  You can’t have koi in a pond that also has rocks and gravel. 


Koi are actually just a fancy variety of carp, and all carp are bottom feeders.  They love to swim along the bottom and scavenge everything that is available on and in between the rocks.  In nature, it’s not uncommon to find ponds, lakes or rivers with rocks on the bottom.  It’s more like their natural environment than an exposed rubber liner, so why even think about doling battle with Mother Nature?


11.  It’s okay to use chemicals in your pond.  


This one comes from the swimming pool industry.  If chlorine is good for humans in the local swimming pool, then chemicals must be okay for fish and the plants in the pond.  Products like algaecide (copper sulfate), dechlorinator (sodium thiosulfate), and fish antibiotics are commonly used as quick-fix solutions to balance related problems.  In the end, your best bet is to attack the root cause of the problem and make sure that you have a naturally balanced pond that allows Mother Nature to take care of all the maintenance issues.

12.  Having a pond may decrease the value of your home. 


Everyone knows when it comes to the resale value of your home, a swimming pool can be deadly.  However, in the opinion of some real estate agents, ponds can be a great addition to your home that might even pay dividends.  With water features becoming more and more popular, you can bet that the demand for them will get even bigger!


13.  I have liability or safety concerns. 


It’s natural to have these thoughts and concerns, but it is important to remember that a professionally-installed water garden has steps leading into the pond.  The first shelf is only ankle high once the gravel is laid down.  The next shelf is up to your knee, while the smallest area in the bottom is just above your knee, so it is not constructed like a swimming pool.  We do recommend that you make your neighbors aware of the water garden and educate your own children and friends about the safety of any body of water.


14.  I want my pond located in the lowest part of my yard.  


It makes sense to have your water garden in this area because it already collects water, however, this is probably the worst location for your investment because of the run-off that can creep its way into your pond.  Ask yourself, “Do I really want my pond located on the opposite end of my property?  Do I really want to miss the sights, sounds and interactive nature my pond presents every day?”  When it’s positioned near your house, you can take in the beauty and tranquility of your pond when entertaining friends or lounging on your deck.


15.  You can use a timer on your pond.  


Not true!  Your pond is a living, breathing ecosystem that needs constant oxygen, just like the human race.  If you shut your system down at night, then you can never have sufficient growth of beneficial bacteria to right algae blooms, and your finned friends will have a hard time breathing. 


16.  It’s necessary to drain and clean your pond regularly. 


The reality is, if you fail to set your system up using the five part recipe so that it’s working in harmony with Mother Nature, then you’ll be asking for a lot of related problems that may require you to drain and clean your pond out on a regular basis.  On the other hand, if you decide to work in harmony with Mother Nature instead of doing battle with her, then draining and cleaning your pond should take place only once a year (at most).  Clean-outs should occur in the spring, before the weather gets warm and the bacteria has an opportunity to set up.


17.  Concrete-lined ponds are better than flexible liner ponds.  


A few pond builders and architects still think it’s “cutting corners” to install anything but more expensive and time-consuming concrete to waterproof a pond.  This just indicates these installers are inexperienced with modern liners and installation methods that easily ensure water-tight, long-lasting ponds.  The truth is we’ve been using liners exclusively for over 21 years on well over 100,000 rock-filled water features.  We find they typically outlast concrete many times because they’re not prone to cracking.  Liner repairs are also much easier than repairing concrete leaks. 


18.  The more filtration, the better the pond. 


Believe it or not, you can over-filter a pond.  Tight filter pads in your skimmer pick up the smallest particles of debris, causing you to be cleaning the filtering mechanism out constantly.  Now remember, we’re not talking about drinking water here.  What we are talking about is water clarity and water that’s healthy for your fish.  Fish in the wild certainly don’t swim around in bottled water.  If you can see a dime on the bottom of the pond, then the water clarity is just right for your fish and filtering past that is overkill and will create headaches, not eliminate them. 


19.  You can’t be a koi hobbyist and a water gardener. 


Not true! You can raise koi and have a beautiful water garden.  There are koi hobbyists who have perfectly balanced pond ecosystems with no chemicals, no sterilization, and a nice assortments of plants.  The koi can grow up to be just as beautiful and just as healthy as they are in traditional koi ponds – and you’ll love them just as much!


20.  High tech is the solution to controlling Mother Nature. 


More than anything else, being observant and learning from Mother Nature is what it takes to be a water gardener.  Whatever she does naturally is what you should be doing in your pond.  Whatever she doesn’t do is what you should be avoiding in your pond.  If there is a golden rule of pondering, it is not to mess with Mother Nature because you’ll lose.

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