Why it is important to know the rules of DE-cholrinating your pond

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Let me start by saying with a choked up throat.  IT HAPPENED — we killed some fish. Koi are my favorite pet and I’m devastated that this happened.

Watch this video to see my dedication for the Koi.

It doesn’t matter how good of a pond builder you are or how well you clean a pond if you don’t know the exact amount of water you put in a pond. Everyone makes mistakes . Hopefully my mistake and loss will teach you not to make the same mistake.

Here is the story on what happened.

We got the call to clean a pond off bee caves road. We made the estimate and was approved for the job. The guy that built the pond made incorrectly (the skimmer was installed just a few feet from the waterfall and not on the opposite  side of the pond, as well as only installing a 5000 gph pump for a 25000 gallon pond) as seen in this picture.

Pictures were taken after the pond cleaning.




So we installed a new pump and waterfall with a bog. We also planted many plants around the edge of the pond. The original builder never added the plants to the pond.



We were able to clean the pond within 8 hours and install the new plants and and mini waterfall to help circulate the pond from the improper skimmer placement. Enough dogging on the previous pond builder. We started to refill the pond but by the time we left at 9pm the pond was only half full. We treated the pond as we always do adding DE-cholrinator to the pond. We put enough to treat 30000 gallons but we put it in at the half way filling point. The next day we continue to fill the pond with new tap water. about 10000 gallons more. And here comes the mistake. Just because we put the proper amount of  DE-cholrinator into the pond it only treated what we added from the day before. DE-cholrinator only works at the time of use, it doesn’t treat the addition water you will be adding the next day. There was enough water in the pond at the time we arrvived in the morning so Iput these 1 foot + gorgeous koi back into the pond. They loved their new pond and could see for miles. But there in the back ground is the hose filling the pond with chlorinated water. As the hours went on one of the biggest started floating on his side. I had no idea the pain I was putting these fish threw. Chlorine burns the gills of the fish and it like an allergic reaction for a human when their throat closes. We pulled them out and tried to revitalize them in a container with good pond water.


The damage was already done and we could only save 1 of the 5 fish.


I was so devastated I used all the profit from this job to buy 35 new koi for this pond. We hope they will grow to be happy and healthy on their way to becoming a dragon. We will NEVER, EVER make this mistake again. We now test for all thing in the pond including chlorine, ammonia and phosphates. We also detoxify nitrite and nitrate as well as correcting the ph balance of your water.

This won’t happen again.


Even thought we accidentally kill this pond owners fish. The customer and I left on great terms and I will be coming back next year to start this all over again. But without killing the 35 new koi we put in.




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