Exactly how you go about setting up and building your goldfish pond will depend upon what type of pond you have chosen to construct; however, the order in which you go about things will be roughly the same regardless.
What do you need to build a goldfish pond?
Depending on the type of pond you create, these materials can vary. Pick and choose what you need for your specific pond; just be sure that the pond is built with secure materials that hold its structural integrity, that the materials are waterproof and are non toxic.
- Pond liner or tote
- Bricks and or cement
- Wooden decking
- Sand / sandbags
- Decor (rocks, substrate etc.)
- Pump and or filter
- Tools to dig out a clearing with (spade / shovel)
How much does it cost to build a fish pond?
The cost of a pond can be hard to pinpoint – every setup will have different initial costs, which are heavily dependent on the types of materials used, where they are sourced and how large you want your pond to be.
Pre-made moulds and totes are going to be significantly more expensive than a “do it yourself” build.
For an example idea, a secure built up decking pond including filter and all, sized around 10ft by 5ft by 4ft could cost somewhere around £200 – £250 ($250 – $310)
Whereas a similar sized pond mould can cost anywhere from £250 – £400 ($310 – $500) and this is just the pond mould alone, not including the other equipment such as filter, pump, substrate decor etc.
If you are going for a budget build, just be sure that the equipment you buy is quality affirmed. Never cut corners when constructing a pond as it can end disastrously.
How to build a fish pond at home
- Mark out surface area
Mark out the surface area that your goldfish pond will take up with rope or string, and secure this in place with pegs to give you a guideline to follow.
At this stage it is very important to be sure that the angle of the floor doesn’t slope and is as flat as possible.
- Remove surface layer
Carefully dig up any turf or surface grass that can be preserved for use around the edges of the pond when it is completed, if you wish. Be sure that the area doesn’t disturb any surrounding structures or neighbouring shrubs / trees.
- Start digging your hole
Start digging! Remove any rocks or obstructions that you come across on the way down, and keep them separate to your piles of earth.
Remember that if you are using a pre-formed pond, you will need to graduate the shape of your hole to match the dimensions of the mould. You should also use sand or sandbags to help fit the mould within the hole as well as provide protection and insulation.
The topsoil and the subsoil of the area that you are digging are rather different in both appearance and quality; topsoil is darker and more fertile, while subsoil is lighter and not so fertile.
You may wish to keep the topsoil separate to use for planting after your pond is complete, just be sure that it is safe and contains no sharp rocks, broken glass or littered plastic which could be toxic.
- Measure the depth
Measure the depth of your pond using a plumb line or tape measure, and ensure that your hole is neither too shallow nor too deep for your pond.
If you are not trying to fit a moult or tote, remember that a pond needs to be at least 3ft deep to prevent freezing and a pond over 5ft deep is hazardous and reduces oxygenation at the lowest parts.
Bare this in mind when selecting your filtration equipment. Also be sure that the liner you use is suitable to handle high pressure and will not tear under the weight of a large pond.
- Check for obstructions
Make sure that there are no sharp edges or rocks protruding into the area that your pond will occupy, as these may compromise the liner or sides of preformed and lined ponds.
- Check the level
Ensure that the sides of the pond are even and not sloped at ground level. Use a spirit level to check this.
Sloped ponds often cause problems like overflowing or freezing over, so it is paramount that the pond does not tip or slope to one side.
- Protect the liner
If you are using a pond liner or a preformed pond mould, protect the material from direct contact with the hard ground by laying down a substrate of either sand, thick newspaper or old carpet. This is not necessary for concrete ponds.
Polystyrene is also a good option for preformed or lined ponds as it provides good structure, excellent insulation and good protection from sharp objects, but is less malleable than sand or soil.
- Build your pond
The next step will depend on what type of goldfish pond you are building:
Always be certain about the construction of your pond, if you aren’t confident in your ability to build a pond it is wise to get help from someone who has experience, you want to build your pond properly the first time to avoid future stress and problems.
How to build a fish pond above ground
Constructing an above ground pond can be quite simple, it involves creating a solid structure for your pond to sit in – this can be any strong enough material, bricks, stone or wood.
This structure should be properly measured, aligned and suited to house a mould or liner, cement or concrete ponds can even just be painted with a water proof sealant, and so can fit any size, with resource restrictions of course.
Between the outer structure and liner should be a layer of insulation and cushioning.
For built up ponds, it is best to use polystyrene or sandbags for this, as they can fit a wide range of shapes, are reasonably cheap and do the job of protection and insulation quite well.
Remember that a built up pond needs to be able to connect a filter or pump – a good thing about these types of ponds is that you can build an extension onto them, which can house an electrical outlet or canister filter, which easily feeds into the main pond
How to build a fish pond with concrete
If you are building a concrete pond, now is the time to get down to the tricky part; laying the concrete and building the internal structure of your pond.
Once the concrete has set and been checked, you can place it in your inner liner or paint the concrete to make it fish-safe.
How to build a cement fish pond
The first step to building a cement pond is to dig out a clearing, as mentioned, the pond should be at least 3ft deep to prevent freezing. Once dug out, you can either purchase a pre mixed cement or make your own.
If you purchase a pre-made mix, make sure that it is waterproof. You can also paint the cement with a water proof sealant after it has hardened, just make sure the water proofing paint is non toxic.
- To mix cement for a pond, use 5 parts sand 1 part cement – mix this and add a waterproofing powder to it.
- Then wet the cement mix until it is the consistency of porridge and begin to pack it directly against the soil in your dug out pond for the first layer.
- Once the first layer is down, create a wire mesh frame and push it into the first layer, this will add extra structure and strength to your pond.
- Once the mesh is in place, add the second layer of cement above it and smooth it out.
- After this, allow the cement to cure, this takes at least 1 week, but the longer you wait, the better, remember to occasionally wet the cement to prevent cracking.
Any cracks that do appear, smooth them out and fill them in with cement.
Once the pond has cured, you can add water, plants and decor as you would any other pond.
How to build a fish pond using preformed moulds
If you are using a pre-formed pond, now is the time to place it into the hole, and make any alterations to the shape of the hole to fit it snugly.
How to build a fish pond using pond liners
If you are using a liner as the base for your pond then lay this over the hole, with at least 40cm overlap at the sides.
Push the liner into the hole, weighing down the edges with rocks to keep it even, and arrange the liner to fill the hole and make good contact with the sides.
When you have filled the pond with water, you can trim off any excess edges of the liner that are left above the sides of the pond.
How to build a fish pond with waterfall
Adding a waterfall to your pond may include a little “diy” activity, however, there are many waterfall features and blades which can be purchased, pre built, which can be simply fitted to your pond.
If you wish to build your own, you need a pump, to draw water from your pond and out through a blade or decoration, and adequate piping which can handle high water pressure. Make sure your electrical outlet for your pump is secure and water proof and that the pipe is fitted securely.
Create a structure from rocks, bricks or wood, build it up from the side of the pond, you want to allow space for a pipe to pass through and or place to install a blade where the water can cascade down in a controlled manner.
Make sure that the water from the feature leads back into the pond and that there is no overflow outside the pond where water will gradually drain out.
How to build a raised brick fish pond
When building a brick pond, first decide on what you want to use to hold the pond, either a pre mould or liner, decide on the size and shape you want the bricks laid out to fit the pond.
- Begin by placing the corner bricks without mortar and butt a baseplate to each corner, then measure the dimensions out, making sure they are straight and to scale using a builders line.
- Stay bars can be used to keep the foundation at an exact horizontal level, be sure that the structure is correctly measured, so that the resulting brickwork will be structurally sound.
- Once you are happy with the foundation structure, place the first mortar bed freehand and begin placing the bricks, aligning them with the rest of the structure.
- Leave 10mm of mortar between each brick and continue this layer by layer until you are happy with the design. Each step, measuring to size and keeping the bricks aligned.
A pointer can be used to finish the mortar and keep the bricks looking clean.
Once the walls are set and allowed to dry, you can then add your mould or begin laying down your pond liner.
- Let it settle
When you have got this far, let your pond settle for a day or two in order to check for any problems, or allow paint within concrete ponds to dry.
If you are confident enough in your design, you can try a test fill up to see if the pond leaks or bows out in any way.
- Fill your pond with water
Fill your pond with water! You will want to dechlorinate this water in order to remove harmful chlorine, chloramines and heavy metals. After this wait a few days before adding any plants, this is to allow the water temperature to settle, chlorine to evaporate and water to become properly oxygenated.
Once plants are added, and the nitrogen cycle has begun in your pond, beneficial nitrifying and denitrifying bacteria will grow in the pond and the filter, which are key to removing harmful toxins.
It usually takes 2 weeks to a month to cycle a pond enough to house fish, if you are a beginner we recommend waiting 3 weeks before adding fish to your pond to allow it time to properly establish.
- Keep an eye on your pond
During the initial week or so after you fill the pond, the water will undergo a range of changes. It may turn cloudy white, brown or green before settling; do not worry about this, this is perfectly normal and your water should settle down within a week or so.
This is just the ecosystem attempting to balance itself – the cloudiness comes from bacterial or algal blooms from a sudden availability of nutrients and an ideal natural environment in which to grow.
After a time, this cloudiness should disappear on its own as it either settles or is collected by the filter. If the water remains cloudy for an extremely long time, like over a month or so, you may perform a water change or clean out your filter.
There are also several chemical products which can remove green water and cloudiness, however, some of these can be extremely harmful to pond life, so be very, very careful to check they are safe for fish, invertebrates and plants!
It is good to frequently test your water – be sure that the pH remains between 6.8 and 8.5 for goldfish and that the nitrites and ammonia stay at 0 or as close as physically possible.
Nitrates can rise to above 50 before they cause discomfort, but an established pond with plants and a good filter will usually manage and eat up nitrates before they reach high amounts.
If your toxin levels are too high, this is usually caused by too much feeding or overstocking, be careful how much waste you add to the pond.