Why Is My Pond Losing Water?

Some water is always lost to evaporation, especially in hot weather. If the level keeps dropping faster than that, there is usually a leak, most often at the edges, in a waterfall or stream, or in the pipework.

Why Has My Pond Turned Green?

Green water is usually caused by tiny algae feeding on nutrients in the water, often from silt, fish waste, fallen leaves or topping up with tap water. Better planting, a clean out, the right filtration or a UV clarifier usually puts it right.

Can You Repair A Pond That Someone Else Built?

Yes. Much of our renovation work is on ponds built by other people, and leaks, failed liners and features that have been switched off are usually fixable.

Will My Fish Be Safe During A Clean Out?

Yes. Fish are moved into holding tanks of their own pond water while we work, and returned once the pond has been refilled and the water has settled.

Is It Better To Repair Or Replace A Pond?

It depends on what has gone wrong. Many ponds can be repaired for far less than the cost of a new one, but where the liner has failed in several places or the pond was badly built, a new liner or a rebuild can be the better choice. We will explain the options once we have seen it.

A pond drained back to its liner and being cleaned out by hand

Pond Renovation · Cambridgeshire

Pond Renovation, Repair And Cleaning

Leaks found and fixed, liners replaced, silt cleared and tired ponds brought back into balance.

Arrange A Visit Call 07568 488223

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Free Site Visits
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Our Own Small Team

Worth Saving

Old Ponds Given A New Life.

Most ponds that have stopped looking good are not beyond saving. A pond that keeps losing water, a feature that has been switched off for months or a pond full of silt and green water can usually be brought back, often for far less than the cost of starting again.

We renovate, repair and clean ponds across Cambridge, Huntingdon, St Neots, Newmarket and Saffron Walden, including ponds that somebody else built. Every job starts with a visit, so we can see what has gone wrong and tell you honestly what it will take to put it right.

Find The Leak

Where Is The Water Going?

Most leaks can be narrowed down at home. Answer two questions about how the level drops and see where we would look first.

Question OneDoes the level drop faster when the pump or waterfall is running?

Yes, mainly when it runsNo, it drops either wayThere is no pump

Question TwoTurn the pump off for a few days. Where does the level stop?

Just below the edge stonesPart way down, then it stopsIt keeps droppingIt does not drop with the pump off

Answer the two questions to see where we would start.

Now Check Where It Stops

With the pump off, watch where the level settles over a few days. That height is the best clue to where the water is escaping.

Where We Would Look First

The Waterfall, Stream Or Pipework

If the pond loses water mainly while the pump runs, the leak is almost always in the waterfall, the stream or the pipework, where water escapes behind the stones or at a joint. We check the lining of the watercourse and every connection.

Where We Would Look First

Around The Edges

A level that settles just below the edge usually means water is escaping at the rim, where the liner has slipped or sunk, or soil has built up against it. Resetting the edge often solves it.

Where We Would Look First

The Liner, At That Level

When the level stops part way down, the leak is usually at that height: a hole or a tear in the liner, often by a plant shelf or where a stone has pressed through. We find it, then repair or replace the liner.

Where We Would Look First

Low Down, Or In Several Places

If it keeps dropping with the pump off, the leak is low in the pond or in more than one place. Draining down and inspecting the liner is usually the quickest way to find it.

Remember that some water is always lost to evaporation, especially in hot or windy weather.

The pump and pipework in the pond before the clean

Finding And Fixing Leaks

If your pond is losing more water than evaporation would explain, there is usually a leak somewhere. The most common places are around the edges, where the liner has slipped or soil has built up against it, in a waterfall or stream, and at joints in the pipework. Many leaks can be found by letting the water level drop until it stops, which shows where to look.

Once we know where the water is going, we repair it properly. Sometimes that means resetting an edge or rebuilding a waterfall, sometimes repairing the liner, and sometimes, where a liner has failed in several places, replacing it altogether.

The pond drained back to the liner during the clean

Clean Outs And Silt Removal

Over the years, leaves, dead plant growth and fish waste settle on the bottom of a pond as a layer of silt. As it builds up it releases nutrients that feed algae, and the water turns green and cloudy. A full clean out removes the silt, clears the debris and lets the pond start again.

We drain the pond down, move any fish into holding tanks of their own pond water, clear and clean the liner, check it for damage and refill. Then we reset the planting so the pond can keep itself in balance. One recent clean out was a large pond that had been neglected for years, where leaf fall had turned the water. Some very good koi came out of that one.

Pond Renovation

What We Offer.

Every part of the job is handled by the same team, so the whole space is finished to one standard.

01
Finding Leaks
Tracing where water is escaping, whether that is the liner, the edges, a waterfall or the pipework.
02
Liner Repair Or Replacement
Repairing a damaged liner where it can be repaired, and replacing it where it cannot.
03
Clean Outs
Draining the pond, removing silt and debris and cleaning the liner, with any fish looked after during the work.
04
Rebuilding Edges
Resetting stones and edges that have moved, sunk or left the liner showing.
05
Pumps And Filters
Checking, cleaning, repairing or upgrading the equipment so the water moves and stays clear.
06
Replanting
New planting where it is needed, so the pond can keep itself in balance once it is refilled.

A toad that has made its home in a pond filter chamber

When Is The Best Time To Clean A Pond?

For most garden and wildlife ponds, autumn is the best time for a full clean. Most wildlife has finished breeding by then, and the work is done before animals settle in for the winter. Partial clean outs and small repairs can be carried out at other times of year where they are needed.

If great crested newts may be using your pond, please let us know before any work is planned. They are protected by law, and work that could affect them may need a licence and has to be timed carefully.

Hosta planted beside the cobble watercourse at Burwell

Bringing A Feature Back To Life

Sometimes a pond or waterfall has simply been switched off because it was leaking or not working, and left that way. At Burwell in the summer of 2026 the feature had been leaking in several places and had been switched off rather than fixed. We traced the leaks, reset the watercourse and built a new stone fall into the pond, and the moving water made a clear difference to the water quality.

Whatever state your pond is in, we will give you an honest view of what can be done. Sometimes a repair is all that is needed. Sometimes it makes more sense to redesign the pond as part of the work, and once it is running well our maintenance visits can keep it that way.

Common Questions

Questions About Pond Renovation.

Anything else, call us on 07568 488223 or see more questions answered.

: Some water is always lost to evaporation, especially in hot weather. If the level keeps dropping faster than that, there is usually a leak, most often at the edges, in a waterfall or stream, or in the pipework.
: Green water is usually caused by tiny algae feeding on nutrients in the water, often from silt, fish waste, fallen leaves or topping up with tap water. Better planting, a clean out, the right filtration or a UV clarifier usually puts it right.
: Yes. Much of our renovation work is on ponds built by other people, and leaks, failed liners and features that have been switched off are usually fixable.
: Yes. Fish are moved into holding tanks of their own pond water while we work, and returned once the pond has been refilled and the water has settled.
: It depends on what has gone wrong. Many ponds can be repaired for far less than the cost of a new one, but where the liner has failed in several places or the pond was badly built, a new liner or a rebuild can be the better choice. We will explain the options once we have seen it.