Ponding 101

Welcome to Ponding 101!
Here we will discuss many things associated with building and maintaining a pond and/or water garden. This will include Frequently Asked Questions and Basic Rules of Thumb as well as conversion charts which will help with sizing.

This page will be under continual construction and additions will be added often.

LivingPonds Construction Guides

Below are inks to different manufacturers construction guides to guide you with some of your pond building needs. The guides are saved as PDF format so that you can easily dowload them. To view this file you need Adobe Acrobat Reader 4.0 or higher. For PC users: To download, right click on file and select 'save target as'

  • Atlantic Water Gardens - Pro Series Pond Kit Instructions Manual.pdf
  • Atlantic Water Gardens - Oasis Series Pond Kit Instructions Manual.pdf
  • Atlantic Water Gardens - Waterscapes Pond Kit Instructions Manual.pdf
  • Aquascape - MicroPond Kit Series Installation Manual.pdf
  • EasyPro - Eco Series Pond Kits Brochure.pdf
  • EasyPro - Eco Series Pond Kits Instruction Manual.pdf
  • Savio - LivingPonds Pond Kit Construction Guides.pdf
  • Savio - Pond Free Kit Construction Guides.pdf
  • Filtration:
    Filter Size:
    To appreciate the beauty of a pond, maintenance needs to be easy and the water needs to look clean. An effective filter creates clean and clear water with only a few light cleanings a year. The smaller the filter, the poorer the water quality. Greater surface area is the key to less cleanings and more efficient cleaning. A proper filter traps light debris, prevents cloudy water and creates a healthy equal ecosystem.  Filter size requirements vary depending on the water temperature, sunlight, stocking capacity, feeding habits, waste loads, cleaning requirements and local water chemistry. For a low maintenance water garden, a good rule of thumb is for the bio-mechanical filter too hold at least 3-7% of the total volume of the pond water in the filter.
    Combined Filtration is the best way to maintain consistent clear water:
    Adding a valve:
    Using bio-logical and mechanical filtration is usually not enough. Adding a skimmer discretely built into the pond edging can drastically reduce the maintenance on your pond. The top layer of water is pulled in to the collection area which traps surface debris before they sink to the bottom. This can cut down bottom waste by up to 85%.  Adding an Ultra violet clarifier (UV or UVC) is another part of the filtration system that will keep the pond looking crystal clear. A UVC is a specialized in-line chamber that exposes unwanted organisms in pond water to a high intensity ultraviolet light. Thus killing most types of algae and clearing the water of green. Avoid getting a pump that is not strong enough. Always select a pump that is one size up from your best conservative estimate and add a ball valve after the pumps discharge. This way you can control the water that is discharged and have a greater overall control. A diverter valve may also be used to divert the water into 2 different sources and to control the amount of water to each source.


    Choosing the right filter...Which is right for me:
    This is a big question that we get presented with all the time. With so many filters on the market; biological, mechanical, pressurized, upflow, bead...you must be going crazy! I will explain the difference here:

    I will start with Bio Filters like the Tetra Clear Choice Filters and the FishMate Biological Filters. These filters sit on the outside edge of the pond. They are noticeable but can be hidden with landscaping or placed under a deck. The water is pushed from a submersible pump up to the filters inlet and then the water spills out and down by gravity. These filters are usually called bio filters, mechanical filters or gravity fed filters. These filters are great for filtering the water and some of the filters even come with a UVC built right in or an option to add one. They usually filter the water with a foam pad or multiple pads of different types such as carbon impregnated filters and a course polyester pad. There are sometimes other media as well for the beneficial bacteria to attach to like plastic bio media balls, lava rock, Supra Media (a natural rock substrate) or the like. 

    Pressurized filters like the FishMate Pressurized Filters and Tetra Pressurized Filters are becoming our most popular filters as they can be buried about 2/3 of the way in the ground which makes concealing them easy. They also have multiple foam pads and a bio media like the bio filters above. And an optional UVC built in on some models. The best thing about these filters is that they can lift water up to a waterfall or stream. They do this because these are enclosed and sealed with clamps therefore when the water is pushed up from the submersible pump into the filters inlet, pressure is built up inside the filter and will push the water through tubing up to a your water feature. It is recommended that you refrain from lifting water more than 3-4ft of total head lift from the filter up the point of discharge. There is another great feature on some of these pressurized filters and that is a unique backwash feature. On the FishMate filters this is called Powerclenz and you would just turn the dial on the top of the filter to discharge the waste from within the filter. On the Tetra Filters it is also a dial like the FishMate filters. The backwash feature explained more in detail allows you to hook up a 2nd discharge tube from the filter to your garden and reverse the flow by just turning a dial or raising a lever on the filter. This will take the waste from the filter and discharge it into the garden or other area.

    Upflow filters are used on the more professional installations. These filters are large boxes that have been engineered to filter your pond very efficiently. They use a filter pad usually made from polyester as well as a bio media that you will usually need to add yourself into a usually included media bag. Here are just a few of the Upflow Filter Models: Savio Living Ponds and Atlantic Water Gardens . These filters are also waterfall boxes. Meaning that when the water is pushed up through the media it flows over a waterfall lip or what is referred to as a weir. There are a few models of upflow filters that discharge the water through a 2" pipe rather than over the weir. You can use an Upflow Filter with a submersible or external pump. They are most commonly used in combination with a Skimmer to cut down on maintenance but the Skimmer is not required.

    Bead filters are the high end in filtration used mostly with Koi ponds or when the pond builder wants a convenient yet excellent filtration device. Also, great for heavy fish loads. The most popular Bead filters would be the Aqua Ultima II Filters. Bead filters are shaped like a barrel and are filled with media beads. Media beads allow the beneficial bacteria to propagate in the filter. These are plastic media with tons of surface area. The  Aqua Ultima II Filters are easily backwashed by the flip of a lever using an internal jet washing system. Bead filters can usually be buried for hiding. Since the filters are sealed they can withstand pressure up to 50PSI (Ultima II Filters) and can push the water up many feet of head lift. You would mostly use an External pump such as the Little Giant Centrifugal Pumps with them although you can also use some of the high pressure submersible pumps like the CalPump Waterfall or the Torpedo Pumps. In your figuring you will want to take off 10ft of head lift for the resistance in the filter. This means that if you are choosing an Aqua Ultima II 2000 you would choose a pump such as the CalPump PW3500, the Little Giant OPWG-46 or the Performance Pro A-1/4-49 If you look at the gallons per hour discharge at 10ft on these pumps you will see that the numbers falls at or below 2000 gph which is the rating the filter.


    Selecting a Pump:
    For healthy filtration the pumps needs to be strong enough to circulate the total volume of water through the filter once per one or two hours. The minimum should be 500 gph per hour. There are many things to consider when choosing a pump:
    Head Pressure: Friction Loss:
    Pumps incur resistance as they move water from the pond to the filter, waterfall or water feature. The water a pump circulates is reduced the farther and higher the pump has to push the water. Gravity create pressure which decreases the pumps output. Pumps are rated for the amount of water they can pump without resistance. A 1000 gph pump is usually at 1000 gallons of water per hour without a pipe connected. (Refer to individual pump flow charts for detailed information) Friction diminishes pump performance as the water travels through plumbing. Every 10' of horizontal travel through pipe is equal to 1' of vertical head lift. Avoid too many curves or sharp angles in the tubing. Do not undersize the pipe or tubing that you connect to your pump and filter otherwise the flow will be reduced. Refer to our friction loss and our Pipe chart below.
    Pipe Size: Waterfall:
    Gallons per hour, not the diameter of the pumps discharge is the way to determine proper pipe size. Many people undersize there plumbing and cheat themselves of the optimum pump flow. Proper pipe size is determined by the maximum GPH capacity of the pump. See Pipe Size chart below. Some people will opt for two pumps when they have a waterfall. First; when you choose a pump for a waterfall you will want to go with this rule of thumb: 1200 gph per foot of width. There are a few differences in which this will vary. (See Waterfall width chart below) You will also want to consider the proper amount of flow required for your filtration system and this is where the second pump comes in handy. Lets say you have a 3' wide waterfall and your pond has a volume of 1000 gallons of water. Well rule of thumb says that you need 3600 gph for your waterfall but just 500 - 1000 gph for proper filtration. You would install a smaller pump for filtration and a larger pump for your waterfall. This is also handy if one of the pumps should breakdown, you will have a spare. Also keep in mind this flow is just a starting point. Personal preference may warrant a larger flow rate. I personally like to go with 2400 gph per foot of waterfall width as it will give a thick waterfall flow.
    Below or Above the water level:  
    99% of the pumps that we sell must be located below the pond surface level. This is called "Flooded Suction". Gravity forces the water into the pump and therefore creating a prime. We do have external pumps that are either self priming or require a priming pot or leaf trap to be operated above the water level.  

     Helpful information on pond pumps and waterfall pumps?

    Installing a Pond:
    Location: Shape:
    When you chose a location be sure the pond will be easily viewed and accessed from the home. Design it to become part of the everyday landscape. Avoid placing the pond under pine or fruit bearing trees. Place the pond in a location that will receive plenty of sun in all seasons. The ideal pond size is large enough to act as the focal point of the yard and dominate the chosen viewing area. Natural shapes are usually the choice for most with smooth curving such as a jelly bean or kidney bean shape. These are generally the most popular. Formal shapes are done to keep geometric form where needed. These shapes would be the round, square or rectangle.
    Bad Shapes: Size:
    Avoid eccentric shapes with sharp curves and niches as these will allow for water stagnation and create excessive folds in the liner which will allow for a build of debris. The most common complaint from pond owners after the pond is complete, is that there pond is too small. A pond shrinks once you add rocks, aquatic plants, landscape, etc. Small ponds can get lost in the landscape. Larger ponds are also easier and less costly to maintain.
    Depth: Underlayment:
    In areas that get hotter or colder then normal, you should consider going no less than 3-5'. For others and in general a good minimum pond depth ranges from 2-5'. Deeper ponds lose less water due to evaporation and stay more stable during seasonal changes and support fish better over the winter. Always allow for plant ledges and keep safety in mind when you have small children. A non woven GeoTextile underlayment will add the extra protection sometimes needed under your liner and will also help with moisture and gases that can accumulate under the liner. Moisture is able to absorb into the underlayment and evaporate out and gases from organic soil material are able to release.  GeoTextile can also be used on top of the liner when you will be placing larger or sharp rocks and boulders that may puncture the liner.
    This is the foundation of your pond. Choose a product that is fish safe, long lasting and that has a good warranty and reputation such as Firestone PondGard. These products are made exclusively for ponds and have a typical life span of 70-80 years. Avoid using preformed plastic ponds as they become brittle and crack usually within just 2-5 years. PVC and Polyethylene also do not provide long life expectancy. Never trust roofing liners or "EPDM Liner". Firestone PondGard liner is EPDM Liner that is manufactured in the USA under specifications that make the product "Fish Safe". Roofing liners are treated with an algaecide that is toxic to fish and plants. Other companies pushing an "EPDM Product" may be pushing a product from another country that just is not manufactured to the United State's quality standards. This is your foundation and should not be skimped on. You would not want to pull up your pond in 3-5 years to replace the liner would you?  


    Sizing Formulas:

    Liner and Underlayment Sizing Formula Determining Pond Volume
    To figure your pond liner size: Take your measurements: Maximum width, Maximum length and Maximum depth. Now take your maximum depth and multiply this number by 2. Take this figure and add 2 for your overhang (this is counted as 1' for each side multiplied by 2). Now take your total and add to your maximum width and add the same number to your maximum length. You will most likely need to round up to match one on the pre-cut liner sizes.

    Here is an example: Maximum width = 5'   Maximum length = 10'   Maximum depth = 2.5'  (2 x's 2.5' = 5' + 2 = 7)  (7 + 5 = 12' width) (7 + 10 = 17' length) So you would need a liner close to 12' x 17' and the closest would be 15' x 20'. You could also back fill, re-measure and see if you can get your measurements to 10' x 15'.

    Rectangular pond: Length x Width x Depth x 7.5 = Gallons

    Round Pond: 3.14 r2 x Depth x 7.5 = Gallons
    (r2 = Half pond diameter times itself)

    Natural Ponds: Length x Width x .8 x Depth x 7.5 = Gallons
    (.8 compensates for lack of corners. Use .85 for ponds 400 plus square feet)


    Conversions Pipe Size
    1 Teaspoon = ~5 ml 100 Drops per teaspoon
    1 Tablespoon = ~ 15 ml  300 Drops per teaspoon
    1 US Gallons = 3.78 L 3 Teaspoons per Tablespoon
    8oz in a cup 2 Tablespoons per ounce
    16oz in a pint 16 cups in a gallon
    32oz in a quart 1/8th = 0.12 HP
    128oz in a gallon 1/6th = 0.14 HP
    1 Gallon of Water Weighs about 8lbs 1/4th = 0.25 HP
    Volts x Amps
    = Watts
    Watts = Amps x Volts
    Undersized pipe restricts optimum water flow. Never select your pipe size based on the pumps discharge size. Pipe sizing should be selected based on the Gallons per hour/minute of the pump. For every 25' of pipe run, increase your pipe size by 1/2" diameter.

    Pump GPH PVC Pipe ID
    0-70 1/4"
    0-150 3/8"
    0-300 1/2"
    300-700 3/4"
    700-1200 1"
    1200-2200 1-1/4"
    2200-3500 1-1/2"
    3500-4800 2"
    4800-9000 3"
    9000-12000 4"


    Abbreviations Fish Stocking
    GPH  = U.S. Gallons Per Hour
    GPM = U.S. Gallons Per Minute
    FPT = Female Pipe Thread
    MPT = Male Pipe Thread
    FNPT = Female National Pipe Thread
    MNPT = Male National Pipe Thread
    S = In fittings this would stand for Slip or Solvent End
    SPG = Spigot - this would be the same outside diameter of schedule 40 pvc pipe and insert the same
    1 - Adult Koi per 10 Square feet of pond surface area or 1 - Adult Gold Fish per 2 Square feet of pond surface area. Consider size. Average size koi and goldfish.

    Rule of thumb: For a well filtered pond 10 inches of koi per 100 gallons of pond water.

    We recommend starting with 1/2 the maximum stocking to allow for fish growth and reproduction.
    Plant Stocking  
    1 - Mature Lily per 15-20 square feet of surface area. Place as many bog plants as desired. If fish are present, cover no more than 70% of the total pond surface area with plants and have no more than one, 1 gallon pot of oxygenators per 500 gallons of pond water.  
    Rocks and Boulders Waterfall Width Chart
    Quantity (approx.) of rocks to use in a 2 foot deep pond:
    Length x Width / 65 = Qty. of boulders used in the pond (tons)

    Example: 10 ft. x 5 ft. / 65 = 0.77 tons of boulders

    Quantity of ˝" to 3" gravel to use in pond:
    Multiply the qty. of boulders (tons) x 0.45

    Example: 0.77 tons of boulders x 0.45 = 0.35 tons of gravel

    Quantity of boulders to use in a stream:
    ˝ ton per 10 ft. of stream length

    Quantity of ˝" to 3" gravel used in the stream:
    ˝ ton per 10 ft. of stream length

    Boulders for Facing:
    You'll need approximately ˝ to 1-˝ tons of boulder to build around the face of your biological filter

    Width of Weir  Thickness of Water

    (GPH per ft)

    Smooth Weir

    Stone/rough Weir

    360 1/4" 3/16"
    600 3/8" 5/16"
    900 1/2" 3/8"
    1680 3/4" 9/16"
    2400 1" 3/4"
    4500 1" 1-1/4"
    6720 2" 1-3/4"

    For streams where the water is not sheeting but rather flowing gently you can use 1/2 of the GPH recommended above.

    Some Common Frequently Asked Questions
    Do I need a filter? How often should I clean my filter?
    If you desire a clear pond you should install a filter. We recommend two filters for water gardens - A mechanical skimmer filter to protect and hide the pump outside the pond and skim the pond of dust & debris and a biological filter to keep the water clear and safe for fish and a Biological filter such as an Up-flow, Pressurized or Gravity Fed Filter. Mechanical filters should be cleaned whenever they slow the flow of water to the pump. Smaller, in-pond filters may have to be cleaned daily, and that is why we recommend larger, mechanical filters like out of pond Skimmers. These are usually cleaned about once a week. It takes about 5 minutes to empty the net and clean the mats. Biological filters should not be cleaned except when they are so blocked that water flow is diminished. A large biological filter, like the Up-flow waterfall type filters are generally only cleaned once per year.
    Do I have to add fish? Do I need a bottom drain?
    No, but fish do eat mosquitoes and are recommended. They are very easy to care for, help eat pond algae and can be trained to eat out of your hand. Fish also add life and color to your pond. Bottom drains promote better pond water recirculation through the filters, so they keep your pond water clearer and safer for fish. They are a must for koi ponds and recommended for any water garden over 3 feet deep or more than 2000 gallons. They can be added to a pond very easily if using an out of pond skimmer or attached to the intake of an external pump. We recommend attaching a bottom drain direct to an external pump. This will guarantee more flow into the bottom drain. When attaching a a bottom into a skimmer you can realize a flow of just 10% on average of what the pump is pushing.
    I have green water...How do I get rid of it?  
    There are three ways to combat green water. First is getting the pond equal and in balance. Second with the use of chemical additives like AlgaeFix. Third with the use of an Ultraviolet clarifier (UVC). You also may look into shading the pond. Plants are the best way to do this and the prettiest. There are also water tints such as Bio Blue. Also, try to not make drastic additions of tap water. The natural salts from the chlorine in the water can feed the algae and create a big algae problem. Instead add water in small amounts and treat the water with a chloramine neutralizer.  
    External Pumps

    1. Locate the pump as close to the source as possible. It is best to have your main (longest) run of pipe on the discharge side of the pump. The pump is designed to push water, not pull it. 2. Install the pump outside the pond, and if possible below the level of the surface of the pond (flooded suction). This will help insure a proper supply of water to the pump. Remember, a pump can not pump out water if there is not any available. Even if your supply line comes up and over the top of the pond wall, it will still offer a flooded suction if it has no breaks to atmosphere before it goes back down below the surface level, and if all air is removed.  

    3. If it is not possible to provide a flooded suction installation then:

    A. Position the pump as low as possible, and as near the source as possible. (A pump one foot above the surface works better than one six feet above the surface.)

    B. Install basket strainer on the inlet of the pump or provide some other priming source.

    C. Suction piping should slope gently upward to the pump or strainer inlet.

    D. Install a foot valve, or a check valve in the inlet line below the water level.

    E. Always prime the entire inlet line, basket strainer, and pump before turning it on.

    F. If your pipe has a high spot (as in lower right illustration), install a tee at the highest spot and use this spot to prime the suction line, (or to bleed off air if pump is higher than the tee)


    The above information is used for guideline purposes only and the information should be verified with a professional before proceeding.
    Safety should always be a #1 concern.
    We will not be liable for any damages caused by misuse or mishandling or any harm caused by the information that we provide above.

    This information is free to use by our customers as a tool in assisting them to purchase our products and problem solve. Others please do not take our information as it is considered theft. If you would like to use the information above on your website or in print, please submit this to us in writing. Copyright 1999-2015 - Jolie Products Inc DBA  123Ponds.com

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