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            Now in our fifth year of business, we have come to realize our philosophy of pond building, specifically ponds that have fish in them, differs from how most other landscape companies in the Okanagan area and abroad would design and build a pond for their client. It differs for a good reason. We don’t want the farting elephant in our ponds!

 

            After hundreds of clients reaching out for one of the above issues in the subtitle we here at Swimming Jewels want to address the proverbial hidden elephant in our ponds — it’s in the design.

 

            The elephant made its way into our ponds during their design phase. From the beginning they can hide in our pond. We will unveil its hiding place throughout this post, but it will take some time. Along with the elephant there is the matter of its farts. Let's clear the air on that issue now. 

 

            Unlike the elephant in the room that may create a metaphorical stench, the one in our ponds literally releases a toxic gas that if trapped for long enough accumulates and when is finally released can be so toxic it could kill all your fish rapidly. The gas is hydrogen sulphide and it is very water soluble. It is also extremely toxic to fish and people. It smells like rotten eggs. It is created from bacteria that have no access to oxygen, anaerobic conditions, that are consuming the sulphates in the debris and accumulated sediment on your ponds bottom and muck trapped in the cracks of the rocks. An excerpt from the book “Advanced Koi Care” by Nicholas Saint-Erne, DVM, 

 

“Hydrogen Sulphide produces the black ooze in the pond gravel, the soil of potted water plants, and bog areas. It has a foul rotten-egg odor and is toxic to humans as well as fish. At high levels, hydrogen sulphide quickly deadens the sense of smell and lethal levels may still exist but go unnoticed. This has caused death in persons exposed to H2S gas. When strong rotten-egg odors appear while working in the pond, take frequent breaks to areas away from the smell to be sure not to become overwhelmed.”

 

            So, the elephant farts are so toxic and stinky the person who is left to clean out your pond may lose a few brain cells, hopefully only the weak ones and thereby making him or her more intelligent and able to question the home owners pond design choices — and well, at times, their own life choices. The blast of toxic stink is sure to get you thinking something is not right, and your correct it isn’t. There is a farting elephant in your pond’s design making all this stink. 

 

            Let’s begin unveiling the elephant that lies hidden in our ponds design. We will discover it hidden in three notable design differences that can be incorporated while creating a pond. The most notable difference in pond design, is regarding the rocks, from pebble to boulder, that are placed in the pond itself, not the waterfall. The second design difference is in pump placement.  The third is in what is considered to be the “filter” for the system. These three differences can play out in many combinations creating various pond set ups.

 

The first is in regard to rocks, our pond design incorporates rocks into the pond’s water but only stratling the surface. Meaning the rocks sit on a flat and level perimeter shelf that is 4-6” below water level. The shelf is created into the landscape before the liner is placed. Then, when the pond is full of water, and the rocks are sitting on the shelf, they become partially submerged appearing as though they are one with the water. 

 

            This design not only hides your exposed liner but creates a natural looking aquatic environment. The spaces between the rocks are perfect for bare root aquatic plants to thrive in as they are in their desired depth of water on the shelf. Given the proximity to the landscape they are are easy to clean.  Other than the rocks used to create the waterfall no other rocks will be placed into the pond. The liner is bare below the surface. Overtime, approximately 2 years, it will grow a beautiful mat of a carpet algae. It never gets more than an inch or so long and turns a black liner into a lush green water carpet.

 

            The difference with rocks in our design from what other companies generally do is they will place boulders and small pebbles throughout the whole pond from bottom to top. Initially, I will concede, this design is visually appealing. It hides not only the exposed black liner above the surface but also the black liner below. It appears finished, but does it age well, like all good things, does it get better with time? I will answer that later.

 

 

The second notable difference is with pump placement, specifically submersible pump placement. Because with a submersible pump the intake for the pump, and thereby pond’s filter, is where the pump is. Unlike an inline pump that can be placed outside the ponds water on land and will suck water from the pond via either a retrofit or proper bottom drain. Meaning for an inline pump the intake for the pump, and thereby ponds filter, are are in two locations. Submersible pumps are the most commonly used on the bottom of ponds and in skimmer boxes so that is what I will focus on.

 

            In general, a submersible pump is either on the bottom of the pond or in a skimmer box. As just mentioned, the pump sucks the water that is directly in front of its intake. The placement of the submersible pump is where the difference is design lies. If you only have a pump that is in a skimmer box then that means only the surface water from the pond is being drawn into the skimmer box when the pump runs. Some debris that falls into your pond floats and will be able to be picked up by the skimmer. If it does not get picked up it will eventually become waterlogged and sink. Lots of other debris and detritus, like fish poop and rotten plant matter, does not float, its is heavier than water therefore sinks. If you do not have a pump or intake on the bottom of the pond then all the heavy material that the skimmer was not able to pick up will settle on the bottom of your pond. If you have rocks in your pond it will settle amongst the cracks of all the rocks and in the gravel on the bottom. Essentially forming a large pile of rotting waste stuck on the bottom with no pump to suck it up and send it to a filter. The accumulated waste creates the conditions for the hydrogen sulphide producing bacteria to live in. The elephant has found a pond to fart in.

 

            A pump on the bottom of your pond acts like the bottom drain of an inline pump. Pump manufactures, like Aquascape, design their bottom pumps to be “solids handling”, meaning they are designed to suck up muck and other solids and pump them to your filter. A bottom pump running 24/7 during pond season that is continually sucking up settled muck and debris and sending it to your filter will keep your pond environment exponentially cleaner than no bottom pump or only a pump in a skimmer box. Which brings us to the second difference. If you were to have a submersible pump in one location, it needs to be on the bottom of your pond where the actual poop and muck accumulates. If your pond is designed with only a skimmer without a bottom pump/intake then it creates the conditions for the elephant to make its way into our ponds and begin farting. Its all in the design.

 

            To combine the first two differences in design, most other companies will place rocks throughout the whole pond, including a gravel bed on the bottom, and only one pump in a skimmer box. All the rocks create thousands of pockets and cracks for accumulated debris and the anaerobic conditions for farting elephants to live in. There is no way to get the heavy settled muck out from the the gravel bed on the bottom of the pond. The gaseous elephant thrives in this condition but it’s gas can become trapped as mentioned above. In contrast to a bare liner pond with a pump/intake on the bottom of the pond acting like a proper bottom drain thereby removing all the settled organics by sucking them up and sending them to your filter. There are only very small places between the perimeter rocks for the elephant in this pond design, and it is easy to remove.

 

The third notable difference is in what is considered to be the pond’s filter. A pond’s filter is its toilet. It is the receptacle in which waste is collected. The toilets, or filters, are all made to be composting toilets, but some are designed so that they can be flushed also. There are three main types of filter that I will touch on; Bog, large plastic waterfall basin, and canister pressure filters. Before I go on to the filter types, allow me to explain the composting effect that can occur in the ponds filter. 

 

            The unseen workhorses in a pond are billions of bacteria. Unlike the bacteria that thrive in the anaerobic (no oxygen) conditions these bacteria thrive in aerobic (oxygen rich) conditions. With the help of oxygen and bicarbonates (alkalinity) these bacteria turn toxic ammonia leeching muck and fish waste into nitrite, which is still toxic and a skin irritant to fish but less toxic than ammonia, then nitrate which is non-toxic plant food. The caveat is they like things a bit warmer. And they need it warm for around 8 weeks before they are really thriving and happy. They don’t like the cold, so they stop working in cooler temperatures.  Unfortunately for them we here in the Okanagan, and in Canada in general, have cold weather for a good portion of the year. That means in colder months there are no composting bacteria turning bad muck into plant food. Just more and more muck, creating the conditions for the gaseous bacteria to live in.

 

            Our spring generally comes in March and once the water hits 10 Celsius the bacteria begin to grow again. Then 8 weeks later they are thriving, but we are now in June. In general, here in the Okanagan we have; June, July, August and likely September of free bacterial labour cleaning our ponds as they compost and turn waste into something beneficial for plants to grow from. Then October comes and they stop working and begin to die off. 

 

            Seasonally, when the composting effect from the bacteria ends and before it begins again the waste accumulates. Without the ability to “flush” the waste in the toilet and no bacteria eating the waste, the waste builds up in the bog or filter media until it is at max capacity then it will simply stay in the pond with nowhere to go. In order to remove the waste, the bog or clogged filter media will need to be flushed or cleaned. Without the ability to flush the filtration media through a backwash system the only way to clean it is with extensive labour and a full reset, which in the case of a bog can be costly both financially to you and environmentally to your pond. That is not to say filters designed with a backwash will never need to be taken apart and cleaned, in-fact they need to be often, but they are designed in such a way that the process is efficient and effective saving time and money. That is why we stay away from purely bog designed filters. Not only are they difficult to clean, even when designed well, as they become clogged and flow is channeled to only a few areas in the bog then the bog becomes a breeding ground for anaerobic bacteria to thrive in. The elephant loves neglected bogs, but we are getting a bit ahead of ourselves.

 

The Third difference then, is the ability to easily backwash or flush the filter or toilet of the pond. As previously mentioned, I will discuss three types of filters starting with a bog, then large waterfall basin, then finally canister type pressure filters. 

 

            The first filter, a bog, relies almost exclusively on the work of composting beneficial bacteria. Many pond designers use a bog as the main source of filtration in the pond. Water from the pump will enter the bog at the bottom through a buried plastic chamber, much like a septic field that disperses the water across a large area instead of out the end of just one hose which can create a channelling effect. The water then flows up through various sizes of gravel, which “filters” the water in the system. The bog relies on composting bacteria to eat up all the muck that gets trapped in the rocks. As the bog become clogged then more channelling occurs creating large areas in the bog that are not receiving fresh oxygen. A home for BIG elephants to fart in.  When the bog is at max capacity it releases vast amounts of H2S gas into the pond and removes little to no waste from the system, all the waste goes back into the pond. Well designed bogs usually have a clean out along with the plastic chamber that allows the owner or pond person to drop a pump down to the bottom of the bog and with fresh water clean all the gravel filled muck in a reverse fashion by pushing it back down to the bottom to be sucked up by a temporary pump. Which only brings us back to the necessity of at one time or another needing to have a pump at the bottom to actually get rid of heavy muck. 

 

            The second type of filter, the large plastic basins that are buried at the beginning of many waterfalls, and usually create a level curtain of water, are intended by many pond designers to be the filter. They are essentially a bog and they usually do not have a drain on the bottom. Unlike a bog that is filled with heavy rocks that are hard to clean, hopefully the plastic basin is filled with a cleanable filter media like Matala mats. Which can be easily removed and cleaned. Otherwise, they may be filled with bioballs or some type of small media that does not allow for easy removal and cleaning as they are designed for increased surface area for bacteria to grow on during composting season. The plastic basin waterfall filters still predominately rely on biological action or the work of the beneficial bacteria to keep them clean. They are designed to be easier to clean than a bog but still with no flushing mechanism rely on costly human labour to clean their filter media. 

 

            The third style of filter is a pressure filter. Which through the turn of a dial reverses the flow of the pump, and depending on quality may require some human labour in the action of pulling a handle up and down, but then cleans the filter media inside and sends the waste water out an alternate port which can be directed to a garden or lawn. Your grass or garden will flourish as the wastewater is genuinely organic and nutrient rich. This style of filter is designed with ease of cleaning in mind, as mentioned earlier some versions will still need to be taken apart often to manually clean the filter sponges but they are designed in such a way that this process is efficient and effective saving you time and money. When the muck in your pond or filter is easier to remove you are more likely to remove it thereby allowing it to remove more muck from the pond creating a cleaner healthier aquatic environment.

 

To SUMMARIZE ALL THREE differences in pond design:

 

ONE - rocks on a perimeter shelf and waterfall only vs. throughout the pond including on the bottom.

TWO - the difference in pump placement between skimmer box and bottom of the pond.

THREE - style of filter

 

 

            The Swimming Jewels Koi Pond design, taught to us by Okanagan Koi, is designed for your fish’s health first and foremost. It is designed to easily keep the bottom of your pond clean and free of debris, which does not allow for toxic elephant gas to thrive in. Parasites that harm your fish also flourish in the muck and over winter can cause life threating skin issues to your fish. The design is also created to age gracefully and become more self sustaining and beautiful as time goes on. It is also designed with the cost of future service hours in mind. 

 

            Now, let’s go back to the question I said I would answer, “how does a pond filled with rocks age?” Well, if it has no bottom pump, no ability to flush its filter easily, then the answer is not well. As the system fills with waste string alage begins to flourish. It sticks to rocks like snot on a screen door. It needs a chemical to dissolve it or a pressure washer to remove it. The waste in the rocks and in the gravel on the bottom begins to produce excessive amounts of hydrogen sulphide gas. The toxic gas dissolves in your ponds water easily which lowers its pH (makes more acidic). As the pH drops you fish are unable to release ammonia within their system. The toxic waste builds up in their bodies. They get sick and in time will perish if conditions do not change. They simply cannot live with a farting elephant in their pond with them.

 

            Many newly built ponds that are intended to have fish in them put temporary superficial beauty over fish health. They will not age well. Homeowners are sold the illusion of beauty with an inferior pond design that will rack up the service hours. “The lined with rocks, only a skimmer and no bottom pump along with a bog style filter and no pressure filter” design will demand countless hours of maintenance to keep clean, which most landscapers are happy to sell you on and charge you for. You not knowing there is another way will oblige to their service as time goes on. Then you come to us one day here at Swimming Jewels. Likely you are having string algae issues, or unfortunately many come with fish issues. We ask you if you have rocks in your pond? We ask about your filter and pump. Nearly every time the answer to your issue is hidden in the design — blame the farting elephant in your pond!