As koi keepers, we have never had it so good. Each year there are more quality koi to choose from than the last, there is plenty of information to support the hobbyist and the standard of pond equipment available has reached a new high.
Most pond liners carry guarantees that will outlive most koi and many pond pumps are sold with lengthy yet realistic lifetimes and guarantees.
A pond pump is the mechanical heart of a pond, feeding the biofilter and UVc with dirty water and providing aeration through waterfalls, fountains and venturis. Without the re-circulating action of a pond pump, the clarity and quality of the pond water and the health of its koi would be at risk.
Koi keeping can be described as a form of intensive fish rearing, where the health, growth and well-being of the intensively stocked fish are at the total mercy of man, completely dependable on his husbandry skills.
Other professional intensive fish farmers would ensure that the life-support equipment such as the pump would be monitored, and linked to alarm system should problems occur. In this way, koi keeping and intensive fish rearing differ (even though the values of stock per tank may be similar). For a koi keeper, the first indication that there is a problem with the pump is the still and quiet ‘air’ to the back garden. Where there was once the cooling chatter of moving water, there is now a quiet, still, millpond-like tranquillity.
Such a scene is a possibility for anyone. Even with such lengthy guarantees, all pond pumps will reach the end of their working life one day, and how we prepare for such an eventuality, will determine our likely response should a pump fail.
Getting to the source of the problem.
If the pump has ‘failed’ there may be a number of causes.
The pump has ‘tripped’ or fused through an electrical fault. Be sure that it is the pump that has tripped out and not another item on the same circuit.
The pump may have become clogged and the impeller entangled with debris. This may result in the motor burning out, but is a factor of the length of time that the pump has been choked.
Burnout. Pumps all have a finite life and will eventually wear out. With most ‘sealed’ pumps, a repair will not make practical or economic sense.
Assuming the worst scenario happens and the pump is irreparable, what is the best course of action?
There are 2 areas that need to be addressed simultaneously.
Securing and installing a replacement pump.
Ensuring good water quality is maintained while the pond is ‘stagnant’.
Securing a replacement pump.
Timing is everything with pump failures and the hotter the weather, the swifter the action required. If the pump had been purchased at your local aquatic store, then you will be in a position to return it rapidly if it is under guarantee. However, this does not automatically mean a swift replacement as the manufacturer’s and retailer’s policy on ‘returns’ will determine whether you are able to take a replacement pump straight away. If the pump is out of guarantee then a straight replacement must be purchased as soon as possible. Try to buy one with a similar (if not improved) performance and one that will fit into your existing system’s plumbing and wiring for a quick installation.
A professional intensive fish farmer would have a replica stand-by pump ready to fit as soon as a problem is suspected or encountered. There is no reason why a koi keeper could not adopt the same policy as it enables a swift replacement within minutes of discovering a problem. However, it does mean purchasing 2 pumps, with the spare pump’s guarantee unfortunately starting from its date of purchase. It may already be approaching the end of its lengthy guarantee just prior to being installed as a spare, but it may be a price worth paying.
2. Maintaining good water quality.
Of course, as soon as a pump’s performance deteriorates, and the flow rate drops or even fails, a knock-on deterioration in water quality also occurs. The warmer it is, the quicker problems will arise. Ammonia and nitrite will rise and DO will drop causing a knock-on change in koi behaviour.
Emergency measures to reduce problems in water quality and stress should include.
a. Emergency aeration. Using a pond air pump (and at worst and aquarium air pump) fitted with diffusers placed as deep as possible with vigorous aeration. This will ‘buy time’ by increasing aeration while a replacement pump is located.
b. Emergency water change. If it appears as though the pump had failed some time ago, then after testing the water, a 30% water change with freshwater will alleviate the build up of ammonia and nitrite. In addition, feeding should be stopped and only recommenced when a replacement pump has been installed and the ammonia and nitrite readings have returned to their original levels.
With a little practical preparation, a potentially catastrophic episode such as a pump failure need not cause your koi too many problems.