Are you building a koi pond and it will soon be over? After everything is finished, of course you want to know right away, is your koi pond safe from leaks? How should you do a leak test? How to deal with a leaky pool?


Building a koi pond is not just making a water reservoir, but what needs to be built also is a chamber that functions as a water filter). There are many techniques for making koi pond filters to choose from, but basically, building ponds and filters are completely separate and only connected by a jumper pipe.

So thus, koi ponds consist of 2 constructions, namely the first is pond construction and the second is filter construction.

Between Ponds and Filters are usually built close together or next to each other which is only limited to a dividing wall. How water can flow from the pond to the filter is because at the bottom of the pond, a bottom drain hole is made, which serves to draw water from the bottom of the pond to go into the filter room through a pipe.


If your pond has just been built, then you must do a water leak test. In addition, even though your pool has been built for a long time, then there is a significant drop in water, you also need to do this leak test.

1st step

For newly built ponds, before filling the water in the context of a leaky pond test, what needs to be done first is to clog the ‘bottom drain’ hole. Likewise for the old pond, move it while all the koi are there and empty the pond water. Then block the bottom drain as far as possible, so that water cannot flow into the filter chamber.

This is done so that the water in the pond and in the filter room becomes separated. Thus, if a pond is leaking, it will be easily detected where the leak is, whether in the pond or in the filter chamber.

2nd step

If a blockage of the bottom drain has been made, then put water into both chambers (both ponds and filters) until it is full. After the water is full, then give a ‘sign’ at the highest level when the water is full.

3rd step

Leave the pond and filter full of water, and do nothing to monitor whether there is a decrease in water level. Observe within a few days whether there is a decrease in water or not.


On the first day, it is only natural if the water shows a decrease, because it is likely to seep in the pores in the cement wall, but the water decrease is not too significant. If the water drops only about 2-5cm from the highest level point, that’s only natural. Wait the next day.

On day 2, the water level should look stable. But if it still drops to more than 5 cm from the highest point, then the possibility of a leaky pond has occurred.

If the level of leakage is severe enough, then in a day the water will drop dramatically. However, if the water drops around 10-15 cm, it means that a small leak has occurred so that the water seeps out.

Continue observing until the next day. If the water level stays down, keep watching until the water really stops falling.

If the water does not come down again, then the point of leakage is on the wall according to the average height of the water line and you easily find where the leak is.

Because the water in the pond and in the filter chamber is separate (because the bottom drain hole has been blocked) it can be observed where the leak is located. In the pond or in the filter chamber?.

Namely by comparing the height of water between the pond and filter chamber. Which one is greater water drop, then in that chamber the pond is leaking.


Especially for new ponds, if every day there is a decrease of water of only about 5 cm, then leave it alone, because it is only due to water seepage. Later after some time, the leak will stop by itself after the moss is attached to the pool wall. So temporarily add water every day to keep the water level stable.

If there is a decrease until the water runs out, it is clear. Means there is a severe leak at the bottom of the pool or filter. Immediately examine again, which parts may be forgotten not covered by cement or usually occurs in pipe joints.

For more detail information can be read on theKOLAM BOCOR article..