koi keeping 5 common mistakes

Koi are relatively straightforward creatures to care for but you can run into trouble if you don't do your homework. Simple mistakes can lead to big issues! Here are the most common errors and how to avoid them.


Koi fish should only be given as much food as they can eat in a couple minutes and they should be fed twice a day. Providing too much food will result in the pond water being polluted by the uneaten portion of food. If you don't have a large filtration capacity, uneaten food and increased fish waste will pollute the water and lead to numerous health issues. In addition, your koi could quickly become overweight.

Overstocking Your Pond

A pond teaming with fish is an exciting prospect and its nice to feature several varieties of koi in your collection. However, it is important to bear in mind that young fish will grow into much larger specimens. This will place greater stress on your filtration system and lead to poor water quality. You should allow at least 600 litres of water per fish and preferably more. If you think that your pond might be overstocked, you must reduce the number of fish or enlarge the pond at the earliest opportunity.

Insufficient Enough Filtration

Under filtering a pond will quickly result in poor water quality. The filter system you have now might not be able to cope when your fish grow and begin to produce more waste. It is vital to monitor your water quality and to act quickly if you think that your system might be failing to keep up with the growth rate of your stock.

Failure to Quarantine

Adding a Koi fish to your pond water without initially quarantining the specimen can see the introduction of parasites, bacterial infections or viral infections to the water. You should quarantine every Koi that you want to add to your pond. That even includes fish that you already own if they have visited a Koi show. Koi can be quarantined in a small trough tank with a filter and the quarantine period should be at least three weeks. If no health issues have developed, the quarantined Koi should be safe to introduce into your pond.

Quarantining also helps your new fish acclimatize to their environment. If the fish doesn't feel stressed it will be less likely to fall ill. It's a good idea to place one additional koi in the quarantine trough. This "canary koi" will introduce the flora and fauna from your main pond and will act as a guinea pig for any issues that the new fish may have brought with it.

Randomly adding medications

You should never introduce medication to your pond unless you are sure that you have correctly diagnosed any health issues. The wrong medication will stress your fish and make the situation worse. It is also essential to establish the correct concentration of medications and of salt, if you add this to your water.

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