Spring pond cleaning
In springtime after the thaw, you may notice that your koi pond looks grungy or unkempt.
This is due to a combination of dead leaves and debris from the fall, and pollen and seeds from the spring. You can clean out the dead leaves in the fall before winter sets in, but you don’t have to as long as you continually check your pond water quality throughout the winter.
Regardless, it is a good idea to clean out your koi pond in the spring. The best time to do it is around April or May. If you do it too early while it’s still cold outside, it’s stressful for the koi and pond fish because they’re not really awake and their immune systems are not at full strength.
It is okay to do it in warmer weather, when the pond water temperatures are in the 70s or 80s, as long as you’re very careful. In this case, when the koi fish are removed for the cleaning, the tub they are placed in must be well aerated and kept in the shade.
If the tub is in the sun or on hot pavement, the koi pond fish can die due to extremely high water temperatures. Given this, the best time to clean your koi pond is when your pond water temperatures are in the 55-65 degree range.
To clean out the pond, you must drain it. If you have gravel in your pond, make sure to stir it up a bit after the fish are removed so that debris is loosened. You’ll then want to vacuum out the pond, making sure you get all the leaf litter and other debris. If you have a strong leaf blower, you can actually use that to remove the leaves.
Do not over clean the sides of your pond especially if they have a nice carpet of green algae growing on them.
The main reason for cleaning you koi pond in the spring is to remove the thick, heavy sludge from the bottom of your pond.
As far as the rocks, they don’t need to be scrubbed. The rocks should have emerald green algae on them which should be left alone unless it is excessively long.
The algae serve as biofilm and philodina, which provide a variety of healthful benefits for your koi pond. If you bleach your rocks, your pond will have to cycle as if it was brand-new and that is stressful for the fish.
In summary, the best time to clean your koi pond is when your pond water temperatures are in the 55-65 degree range. Use care when removing your fish during the cleaning so that they do not become overheated. Vacuum or blow out all debris in the pond, but do not remove algae from the rocks as it is beneficial to pond health.