Often times we see pond liners with over 10+ years of use leak rather easily due to roots, people walking in the pond, or simply deterioration. What we like to do to determine if the koi pond is truly leaking is what we call a "draw-down test" this test is very simple to do and can determine where your leak is within a few days of your testing beginning. 

First – If you are unsure if your pond is facing an emergency, we recommend calling a professional koi pond repair company. Fill your koi pond up to a safe level (without diluting your pond with tap water of course) and mark a spot to be able to recognize where you last filled your pond up to. This is important as its easy to lose track of where your pond was filled to in the previous days to follow. 

Second – If you have air-stones or aerators we suggest using these during the second process of your koi pond repair as it requires you to shut your pump off. Air-stones are little air pumps you can buy at a local home depot or pet shop for around $50-$100 and will help your fish breathe during the second process. Once your fish are safe, turn your waterfall, pump, and anything else moving water off. Let the pond sit for 24 hours before adding water or turning your pump on again. 

Third – After 24 hours we suggest noting how much water loss has occurred. Anything beyond 1/4″ is excessive and should be investigated further. If you have not loss any excessive amount of water, your pond is fine and you can go back to enjoying your koi pond. 

Fourth – Is your pond losing water beyond 1/4″? If so let’s move forward, we will now determine if the issue is your waterfall or the basin(s). If your pump is off, we are isolating your basin(s) to see if the water level drops in 24 hours, if so – we will know this is where we are losing water and wait until the water stops dropping (unless your fish are in danger) once the water has stopped dropping you will know at which level the liner is broken and needs to be repaired. 

Fifth – Not losing water in your basin(s)? Lets isolate the waterfall now – this can be done by purchasing a 2″ pool hose (only need the length of the waterfall to basin) and connect this hose to your waterfall upflow hole. This is a threaded 2″ hole your hose can fit into. Doing this will bypass your waterfall area and rule-out the waterfall being the culprit.



Sixth – Once you have connected your hose to the waterfall you can once again fill the pond up, record the level, and turn your pond on. Let it run for 24 hours and note the difference in level once again at the 24 hour mark. 

Seventh – Did you pond not lose water within this 24 hour-span? Your waterfall might be the culprit if so. Consider letting your waterfall run this way for another 24 hours, if you have not lost water in the additional 24 hours consider removing the hose and running your system normally, if you are losing water – your waterfall needs to be repaired or rebuilt. 

Lastly – Still losing water or not sure what the issue is, might be time to have a profession handle this koi pond repair? Call someone who knows how to build a waterfall (714)613-0123 

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Koi Pros

Address - 529 W Blueridge Ave #F110 Orange, CA 92865

Phone - (714) 613-0123

Email - KoiProsOrangeCounty@gmail.com