Everything first-timers ask us before the shovel hits the dirt. Planning, digging, liner, equipment... it's all here. Read it once now, then come back when you're standing in a hole wondering what's next.

How do I get started on building a pond?

Two decisions, in this order.

First, location. Put the pond where you'll actually see it: near the patio, the deck, the porch, or a kitchen or living room window. Sunny is nice. Visible is better.

Second, size and shape. Lay a garden hose or a string on the ground and live with the outline for a few days. Then decide between a rigid pre-formed pond and a flexible liner.

Sun or shade?

Enjoyment wins. Pick the spot with the highest visibility, even if it costs you some sun.

Six hours of direct sun is the ideal, and it will get you more and better flowers. But the sun is for the plants, not the pond. If your best viewing spot is shady, build there anyway and choose shade-tolerant plants. Plant leaves shade and cool the water below... shade from trees above does the same job for water quality.

Should I build large or small?

Budget and space set the limits, but the pond should fit the scale of your landscape. For reference: a large water garden is about 1,500 gallons or more, roughly 10' x 13' x 19" deep. Small is anything under that. Many starter ponds run 200 to 500 gallons, and a patio pond can be as little as 50 gallons at 18 inches deep.

Here's the pattern we see constantly: people build small, then say "I wish I had built this larger." The good news is small ponds expand easily. Dig the original bigger, or add a second pond connected by a waterfall.

Can I put the pond in the low part of my yard?

It looks like the natural spot. It isn't.

If you have a high water table, plan for drainage tile or similar provisions before you dig.

Can I build a pond in the winter?

You can build anytime the ground is diggable. If the soil is wet or frozen, wait until it's workable. That's the whole rule.

How deep should my pond be?

For goldfish and water plants in the temperate United States, 18 to 24 inches. Deeper than that buys you nothing for overwintering plants or goldfish.

• Water lilies want at least 10 inches of water over the soil surface, and prefer 10 to 20 inches.
• Bog plants vary. Check the depth chart for each plant.
• Koi are the exception: they need steadier temperatures than shallow water provides, so a koi pond should be at least 3 feet deep.

Should I build plant shelves into the sides?

Shelves work well for potted plants. Make them at least 10 inches wide and 8 inches below the water, larger or deeper for bigger pots and deeper-growing plants.

Put shelves at the back and sides, not the front. Tall plants along the front edge block your view of your own pond.

The more natural-looking alternative: plant into the edge stonework. Tuck bare root plants into gaps between stones, or fill larger openings with soil for bigger planting pockets. No round pot sitting on a shelf... just plants growing out of the rock.

Should I line the bottom with rocks?

Rocks on the bottom hide the liner, and that's about the only thing going for them. Cleaning around bottom stonework is messy and slow, and algae-covered rock underfoot is genuinely treacherous when you wade in to prune and fertilize lilies. A smooth liner bottom is easier for the long haul.

Liner or pre-formed pond?

Most people go with a flexible liner: any size, any shape, any depth, with a lifespan comparable to the best rigid fiberglass at much lower cost. Standard 45 mil EPDM rubber is the liner of choice.

Pre-formed rigid ponds still earn their keep in two places: as a beginner's first pond, and above ground, where soil gets built up around them. A pre-formed header or spillway pond is also a great rigid starting point for a waterfall.

If pre-formed, fiberglass or plastic?

Fiberglass is the strongest, and it's the one to use for raised ponds where the shell has to support itself. It costs more.

Plastic is the budget option, but it can't stand free. Building up soil evenly around a plastic form is difficult, and uneven support risks cracking it. Plenty of people start with a cheap plastic pond, then upgrade to a rubber liner later.

If a liner, rubber or PVC?

Rubber. Specifically 45 mil EPDM. It stays flexible across a wide temperature range while PVC stiffens in cold weather, and it shrugs off sunlight while PVC turns brittle in a few years. It comes in many pre-cut and custom sizes. PVC is cheaper, and that's its whole argument.

What goes under the liner?

Underlayment: a heavy fabric that pads the liner and protects it from punctures during installation. An acceptable alternative is underlayment on the sides and about 2 inches of sand on the bottom.

Do I need concrete for the stonework?

Avoid it wherever you can. Good stone-setting practice makes a rock edge sturdy without masonry. Concrete has a place edging a formal pond, but a natural water garden doesn't need it.

What about concrete in the waterfall?

Same pH problems as above, plus a design problem: a concrete waterfall has to be built dry. You don't see how the falls actually look and flow until the concrete has set... and by then you can't change it. Build the falls without concrete, with the water running, so you can adjust as you go.

Can I repair a cracked concrete pond?

It's challenging, especially where winter frost heave is a factor. Masonry patch materials dry rigid and usually crack again. Aquata-poxy, a two-part, solvent-free, 100% solids epoxy coating, covers cement block, brick, and cracked concrete, and applied per the instructions it makes a long lasting repair. The same coating will make a wooden planter watertight, if you'd rather grow a pond in a barrel.

Can I build an above ground pond on my patio?

Yes, and there are real advantages: less bending during maintenance, easier viewing, and a safer setup around small children.

The catch is winter. In zone 7 or colder, a small patio pond can freeze hard enough to kill plants and fish, so it needs a floating heater. In warmer climates a short, light freeze won't build enough ice to harm anything.

How do I run water through the side of a pre-formed pond?

With a bulkhead fitting: a watertight fitting that passes through a pre-drilled hole in a fiberglass or plastic wall, with a gasket on each side. A large nut compresses the gaskets tight, and rigid PVC pipe or tubing connects to the fitting to carry the water.

What size pump do I need?

The goal for most ponds is turning the full volume over about once an hour. A 1,000 gallon pond wants roughly 1,000 gallons per hour actually moving through the system.

Here's the first-timer trap: the GPH number on the box is measured at zero head... water pushed straight out of the pump with no lift, no tubing, no fittings. Your pond is not that. Every foot of lift costs flow, and so does every foot of tubing and every elbow.

Figure your real head height like this:

• Start with the vertical rise from the pond surface to the highest point the water reaches (usually the top of the falls).
• Add about 1 foot of head for every 10 feet of tubing run.
• Add about 1 foot for every couple of sharp elbows or tight fittings.

So a pump lifting water 4 feet through 20 feet of tubing with a few elbows is really fighting 7 to 8 feet of head, and a "2,000 GPH" pump might actually deliver 1,200 to 1,400 GPH. Good pumps publish a flow chart showing GPH at different head heights. Read the number at YOUR head height, not the headline on the box.

Should I use a skimmer?

For ponds over 1,000 gallons, absolutely. The pump sits inside the skimmer box and vacuums the surface, catching leaves, pollen, and grass clippings in a net before they can sink and rot on the bottom. Bonus: the pump is far easier to reach for service than one sitting at the bottom of the pond. Skimmers work in smaller ponds too, they just eat up more room than some people want to give.

Can my waterfall be a biological filter?

One of the best. All that wet, irregular stone surface is exactly what beneficial bacteria colonize, and the constant flow keeps them fed and working, processing organic pollutants out of the water. Suspended soil and debris settle out as water moves over the falls, and the water picks up oxygen on the way down. Those are the essential components of a manufactured bio-filter, just in natural form.

It only works while water moves, though. Circulation is the delivery truck: it carries oxygen, waste, and bacteria to where they're needed. Still water can't regulate itself, and stagnant corners are where debris and algae get their head start.

How do I build a waterfall on flat ground?

Start with a pre-formed spillway or header pond: a rigid pond with a spillway built into the rim. The soil mounded around a waterfall settles over time, and a rigid header keeps the water flowing where you aimed it instead of wherever the settling sends it.

What about a waterfall on a hillside?

Keep it proportionate to the surroundings and to the pond it feeds. Whether it meanders down or runs straight in is a design call... yours.

Do I need a GFCI outlet?

Yes. Any outdoor receptacle must be protected by a ground fault circuit interrupter. It cuts power instantly if the electrical system fails, and around water that's the difference that matters. GFCI protection installs in place of a standard outlet, or comes built into an extension cord (but don't plug a GFCI cord into a GFCI outlet).

How do I keep my upper pond from draining when the power goes out?

When the pump loses power, water can siphon backward from the upper pond to the lower one through the pump and tubing. The fix is an in-line spring check valve: a spring-activated fitting that automatically plugs the line when power is lost and holds the water in place until it comes back.