Well, it looks like you have a leak in your koi pond. Repairs need to take place, but you have several lovely fish that call the pond home. You can’t very well repair it with them still in the pond, so you need to move them. However, you need to keep in mind that moving the fish from one location to another can be very stressful for them, so you need to be as careful as possible.
The fish in your pond are already stressed out because of the leak. If the water levels are going down, it is changing quite a bit about the ecology in the pond, and this causes stress. When you move them, this adds more stress, and this can make them more susceptible to disease. You can reduce this possibility by taking the right precautions before you move them for the koi pond repair.
Prepare the Water
You will want to prepare the water for your fish before you have to move them. You can take water out of the pond where they are currently and place it in the location where you will be keeping them, but you want to make sure it is free of debris. You can also prepare another location ahead of time.
A good way to reduce stress is to use some of the water from your pond in the location where you will be keeping the fish. This is helpful because they will not have to adapt to a new water chemistry, which can cause even more stress on their bodies.
A Safe Place
Ideally, you will be keeping the fish on the property, and they will not have to travel very far when you complete the koi pond repair. Prepare the location early, and have a good and safe way of transporting the fish. Unless you are very practiced at netting and moving fish that can get as large as koi, don’t do it. Simply putting them in a net can injure them. Instead, you can use a net placed beneath them to “guide” them into a bucket of water.
Then you will carry the bucket and the fish to the area where you will be storing them during the koi pond repair. This can take a long time, but it is less stressful for the fish. Just make sure the pail is deep and the water is low enough that the fish can’t jump out.
Wrangling the fish for a koi pond repair can take quite a bit of time, and it is generally a good idea to have more than one person helping. One can guide the net and the other can hold the bucket. Go slowly and do your best to make the transportation as easy as possible on your fish.
Once they are out of the water, you will be able to drain the pond and take care of the leak properly. When you return them, use the same procedures. You can keep your fish healthy when you take your time.