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Building a Pond

Building a pond

1. You may want to outline the area for your pond by using rope or stakes first to get an idea.

Getting the edges of your pond all level is important otherwise you'll end up doing a lot of camouflage work to cover up the high sides of the liner. (I saw gadgets in a Pond Supplies of America catalog that attached to each end of a garden hose that allowed you to level over long distances. I really wish we had had them. Trying to level with strings and sticks is for the birds. Next time (and I'm sure there'll be a next time) they will be a necessity.

Liners can be gotten from pet stores that have aquarium sections or one can be made from rubber roofing material
(check your yellow pages for roofing contractors - you might get lucky and find one who has a large piece left over from a job). (There are several places that sell large liner materials rubber (60 mil thick). Liners can cost from $100 to around $300, depending on size, type, etc. I kinda like the rubber because you can cut and glue it to pretty near any shape you want. With the regular pond liners one is confined to whatever size is bought.

Also many ponds are cement lined and smaller ones often use a pre-formed fiberglass shell. Essentially what it boils
down to is a hole in the ground lined with something that will hold water.

If it's put in an area with trees or where rocks work their way to the surface, you oughtta line the bottom of the hole
with something to protect the liner so the roots/rocks don't poke a hole in the bottom. Several inches of newspapers and/or old rugs work well. Probably a good idea to do it anyway. It acts like a buffer between the weight of the water pressing down against anything that might work its way up/under the liner.The pond should be deep enough so the bottom is below the frost line in winter so the fish won't freeze. But if it isn't, you can always put in a small heater to keep a small area open. I've never used a heater and swear that one bitter cold spell it froze clean to the bottom (it was 18" deep then, it's now 30"). You could actually see the fish frozen in the ice. I only lost maybe 10% of the fish so it really didn't bother them all that much.

In the bottom of the pond put white gravel (I recommend 3-4" deep). It does four things:

1. It vastly increases the surface area for bacteria to grow on that break down fish wastes, water discoloring algae, and other organic matter. (See UG filter further on)

2. It provides a base for plant life to root in.

3. It gives the fish something to root in for food (algae)

4. It provides a light background to look into - You'll be able to see the fish and other stuff a lot better.

Finally, a rule of thumb is, "Bigger is better". No matter how big you make your pond, after a while you'll probably wish you had made it bigger. Another advantage is that the more gallons, the larger the buffer for environmental changes. For example, it warms/cools slower, allowing the fish time to better adapt. Generally it's not much more time consuming to take care of a large pond as a small one.

The Filter System

It's important here to remember one rule - The filter(s) can only be too small, not too big. If you don't mind green or cloudy water, and only want a few fish, you can ignore this rule. Generally the more filtration, the more life you can support. If your pond is in direct sunlight it will generate a lot of algae and become nearly opaque
without a good filtering system.

Essentially filtration boils down to three kinds:

1. Mechanical - which physically removes matter from the water.

2. Biological - which uses bacteria to break down matter (particularly ammonia) into stuff that can be utilized elsewhere.

3. Chemical - which kills algae and bacteria that would otherwise discolor the water.

The explanations are simplistic but functional enough for this discussion. One other thing, when I'm talking about algae, I will generally mean the water borne kind that discolors the water, the kind that biological filters take care of. There are all kinds of algae and the kind that grows on surfaces is generally good for the pond and provides food for the fish.

The absolute best filter I have found is a lava rock system. Lava rock is very porous (it's so light that some often float until they soak up water enough to sink ). All that surface area will get covered with good bacteria to break down the ammonia from fish waste and eats the algae that colors the water green. (Actually it uses the nutrients algae needs to get established.)

Further it makes a dandy mechanical filter as well but that's not its primary function. There are some that claim to having more surface area than lava rock, or work better, but those claimants are usually selling something more expensive. Lava rock is pretty cheap at garden centers.)

You can also make a filter out of a fifty five gallon plastic drum and a submersible sump pump (1200 gph - $65 at Rickels, $5 at a garage sale). It's pretty easy.. here's how.

1. Cut out the top the drum so it is open.

2. In the bottom, put an 1 1/4" drain with a length of pool hose attached to it. Make sure you use at least 1 1/4"
as it makes cleaning a breeze. Fashion a hook or use twine to hold the free end of the hose above the top of the drum.
(You could put a valve on the bottom as well but the hose is a lot cheaper and much easier to use.)

3. Put a milk crate inside on the bottom and a grate on top of it. You can make the grate out of heavy plastic coated 1/2" wire mesh. I used a light diffuser from a fluorescent light fixture. (You've seen them, made out of white plastic, 1/2" squares. It's called egg crate.)

4. Put a 1 1/4" fitting for the input hose in the side of the drum (you can use a 1" fitting just fine but the 1 1/4" allows for a bigger pump later on) just below the level of the grate . The space between the grate and the bottom provides a settling area for dirt, etc. before the water percolates up through the lava rock.

5. Put an 1 1/4" discharge fitting near the top of the side of the drum for the filter outlet. You may need 2 depending on your water volume. You ought to leave it 2 or 3" below the very top so that it can build a little pressure if it tries to overflow. If you decide you need two they are better one above the other rather than side by side. Or you can just cut a slot and fasten a piece of liner to the barrel to act like a chute for the water to exit through.

6. Fill the drum with lava rock ($5.35 a cubic foot at a local landscape center/) to about 3 or 4" from the bottom of the filter outlet. You'll probably need 4 or 5 bags. When the drum is filled with water, put water hyacinth or something else fast growing on top of the rock. The roots provide additional filtering and it makes a nice cover.

1. The floc settlement area, should be at least 2" between the bottom of the discharge pipe and the top of the lava to
keep the floc from going into the pond. ("Floc" is matter created by the algae, analogous to feces)

2. The discharge pipe(s), must be a lot larger than the input pipe. The water is coming in under pressure
(greater than gravity) and is leaving under gravity. I have two 1-1/4' outlets here. You don't need pipes, you could just cut a hole in the barrel here if you wanted. Pipes worked out much better in my application.

3. The area filled with lava rock . The deeper this is the better, mine is about a half or more of the barrel.

4. The grate the lava rock sits on. You'll have to imagine the milk crate it sits on to hold it off the bottom,

5. The input pipe from the pond. Mine is 1", which was plenty big enough for my 2,000 gph sump pump after going
through about 20' of pool hose (but not for my 3900 gpm).

Make sure you locate the input JUST BELOW the grate the
lava sits on. If you put it too close to the bottom, it will defeat the purpose of the settlement area and keep the dirt stirred up and clog the lava much sooner.

6. The settlement area for heavier pieces of dirt. Mine is about a third or a little less of the barrel. This height is not critical but shouldn't be more than a third of the barrel.

7. The clean-out drain. Mine is 1-1/4". DO NOT use less than 1 1/4" here, even if you are using a small barrel or
bucket. Filter flushing is just SO MUCH EASIER, FASTER AND BETTER with a large discharge it is a foolish economy
to use anything smaller.

There you go, the filter is done. Whatever you do, use as large a pump as is practical. A rule of thumb I use is to turn the pond over at least once an hour, more if possible. This is NOT cast in stone. You could always start with a much smaller pump. It's been my experience that a great flow is not needed for the bacterial part of the filtration. It is nice to have a large flow for a waterfall though.

My submersible sump pump is inside a small bucket with a grate (egg crate is good) fitted over the top of the pump with a layer of stones (lava rocks work well) on top of the grate to keep fish from swimming through the grate.

With the pump inside the bucket, it also provides a measure of protection for your fish and plants two ways:

1. In case of a major leak outside the pond (broken hose, etc.) as the water level won't go below the height of the

2. Protection from fish and plants being sucked into the pump (been there too - hence the large stones instead
of matting).

When your water flow slows down (or more often) drop the drain hose of the main filter and flush the lava rock from the top until the water runs clean. I discharge into a garden area, good fertilizer you know. Only takes a couple minutes.

The larger your filter(s) the less often you'll have to clean it. And generally it doesn't take any longer to clean a large one than a small one.

It's important that your cleaning process be a simple one. If it's a pita to do (say has a small drain that doesn't allow for easy flushing and takes forever to drain), it won't get done as often. What happens then is stuff will get packed in the lava rock so tight, you'll have to remove the rock to clean it. And that's a real pita.

If you see the water "channeling" up through the lava in places, you can be pretty sure it's starting to get plugged.

Don't put off cleaning it I channels. It isn't working well and can only plug harder making it more difficult to flush.

Channeling also means the area of lava rock exposed to the moving water has been drastically reduced.

And there's no rule says you have to use a barrel either.An important fact to remember is that as water warms it rapidly loses its capacity to hold oxygen. I don't know the actual numbers but it is dramatic, almost logarithmic, something like holding 2 or 3 times as much oxygen at 50 degrees as it does at 60 degrees. And the warmer the water gets, the less oxygen it holds, so aeration is important (even critical), especially if you're like me and like high populations of fish.

The water gets thoroughly aerated and re-oxygenated falling down the 4' high wall of rocks. This is healthy for the fish and is another form of filtration (oxidation) as well. Our wall gets lots of sun and what happens is that algae builds up on the rocks and seeds from our hanging impatiens drop and bloom in the algae (even more filtration. Looks pretty neat too).

Another idea is to lant Parrot Feathers on the top and let them grow down the front. They grow like ... well ... weeds and completely cover the waterfall. andl ooked pretty neat too.

You could also locate the filter some distance away and build a stream meandering back to the pond. If you do that, make sure to put plenty rocks in the stream bed to disrupt the flow to get better aeration.

For a really rough gauge, you can figure to get 25-30 square feet of coverage from a pallet of flat landscape rocks (like slate). 'Course you could get a lot more or a lot less too, but it's a ballpark.

Locate your pool in sunlight if possible, the water lilies will flower much better in direct sunlight. The pond inhabitants (fish & plants) are just so much more attractive in the sun too. Positively sparkle. Be aware of trees - leaves gotta fall somewhere. You probably ought to have the sides a little higher than the surrounding land so as not to get runoff (probably contaminated with lawn fertilizers and herbicides) into the pond.
You might want to taper the sides of your pool to provide a slope for plants and stones for a more natural appearance. Or you could put a step (6"- 12") from the top to hold potted plants. Or ....

If you use a waterfall or put rocks around the edges of the pool, extend the rocks 6-12" below the surface.

They'll provide lots of little caves and crannies for the fish to hide and play in.

As far as fish goes - you can spend anywhere from $.10 each for feeder goldfish to five, even six, figures each for fancy imported koi. I'm partial to 10 centers . Put a few dozen in and at least 80% should survive initially (feeder fish are not bred for their longevity and are often weak when you get them). Of the ones that do survive the first few weeks, many will last several years and grow quite big. And with any luck some of them will have long flowing tails. At any rate don't put too many or any expensive fish for at least a month or more. Give your filter time to build up bacteria and the water to "mature" a little.

It takes a year for a pond to "develop" and start to
look like a pond.

Otherwise almost any member of the carp family will do well. Koi, shubunkins, ruyakins, orandas, and comets will all survive cold winters nicely. Winter mortality is usually well under 10% and is often 0%.

If you live in a temperate area where the water temp doesn't go below 60 degrees you can use pretty much any kind of tropical fish.

Put some tadpoles in the spring. It's fun to watch them develop into frogs. The frogs will winter okay if they can burrow into the bottom somewhere.

An advantage with 10 centers is that you can over populate, they will find their own balance and you won't be out big bucks. Nothing hurts more than to lose a $10 or $20 fish.

As soon as the water warms up enough (60's), you can usually put a couple bucks worth of feeder guppies in. They thrive and multiply like rabbits all summer and into the fall Cold water gets em though. Feeder minnows too. They add variety and interest.

If you have small fish and put in a small channel catfish, you'll end up with a huge channel cat and a lot less fewer fish.

Primarily you can feed your fish Friskies cat food. It's cheap and nutritious. Every once in a while, throw in a Milk Bone. You can give them normal fish food too but that's like a treat. Any time u don't see anymore Friskies floating, throw in another handful. Winter time too though
they don't seem to eat near as much. I've heard a lot of claims about only feeding once or twice a day and then only as much as they'll eat in 2 or 5 minutes but I don't subscribe to it . Under that theory, the big ones get to eat the most and the little guys hardly get anything. My way they all get as much as they want (and with much filtration you don't have to worry about overfeeding {grin}.

You can also make a mixture of: a cup of Tetramin Fish Flakes, a handful of Friskies, a couple handfuls of some puppy dog food that looks like gray Cheerios, a couple handsful of Tetramin Floating Pond Sticks. The Friskies and pond sticks float, the "cheerios" sink and the flakes do both. That way all sizes get something and a good rich varied diet. They get a handful of this once or twice a day or more.

Many people have two ponds (or even more) connected with one higher than the other. The water is pumped from the primary pond into the secondary pond that acts as a settling filter. The secondary is often very shallow with dirt and gravel in the bottom and lots of plants. Some are even planted to look like a marsh bog with cattails and stuff.

Gravel Filter Diagram

Essentially they are under-gravel filters just like those used in aquariums. Take 2 pond lengths of 1 1/4" PVC pipe and drilled them full of 3/8" holes and laid them on the pond bottom, each with an elbow on one end pointing up and a piece of pipe long enough to be about 6" below the water surface when the pond is full.

Synthetic matting was laid on top of the pipes and the gravel on top of the matting. (You can use almost anything that's water permeable.)

I prefer matting because it adds just that much more area for bacteria to grow but you could even use plastic or nylon window screening on top of a more rigid plastic mesh (just not a metal that will eventually rust or corrode).

The reason for the rigid mesh is that you don't want the screening to wrap around the pipe when you put the gravel on top. It's okay if it "tents" over the pipe, just so it doesn't wrap tightly. The object is to increase the "draw" area as much as possible.

From your local aquarium store, pick up a "power head" for each pipe. or mail order from That Fish Place (800-733-3829) for $17 apiece. 300 gph each (NOT larger - don't want too much suction through the gravel).

Power heads will fit nicely on top and inside of 1" & 1 1/4 " pipes. cut pipes so the tops of the pumps are 2 or 3 inches below the surface. They provide an almost imperceptible surface current providing an even greater oxygen interface exchange.

They are cheap and easy to put in (even if unnecessary overkill) so why not do it If you stick the pipes in when you're building it, it's almost no additional work. You can add the pumps anytime. You could even use aquarium air stones instead of power heads to pump the water as well (might even be cheaper and would provide even further aeration).

Another suggestion of using a laundry sink for a filter at the top of and behind the waterfall. It already has the drain on the bottom. I'll bet you could find them pretty cheap in junkyards and second hand stores.

There are chemical additives to keep the water clear but I suggest stay away from them. If they kill the algae (a living organism) then what do they do to plants and fish? The closest I would come to that is to put 10 lbs of sea salt ( NOT NOT NOT table salt) in once a year. It's supposed, and seems, to be good for the fish. (If you notice a couple fish getting lesions and are out of Sea Salt try "natural" salt (made from evaporated water, not mined like rock salt) put a bag in and the lesions should clear up after a couple weeks.) (In the winter if losing fish to lesions again you may need to come to the conclusion it's because of the water source. remember city water is (chlorinated) and a well water could also be loaded with herbicides, etc. So you may end up putting a medicine in.