Voltage fluctuations such as an unusually high or low voltage before the outage, a damaged plug socket, or a lost electrical supply are three reasons why a fish tank filter isn’t working.
High voltage fluctuations (which may only occur momentarily) are enough to cause permanent damage to a fish tank filter.
These fluctuations are a common occurrence alongside power outages in our experience.
Contact the local company which manages the power lines for more information on what has caused the outage. The main components of the fish tank filter system affected are the motor and any electronics (if any).
The aim of this post is to explain different reasons why the fish tank filter isn’t working from an electrician’s point of view.
Fish Tank Filter Wiring & Fault Finding
A fish tank filter contains a small electric motor. This motor is designed to operate at a steady, standardized voltage range. For the USA this is 110-120 volts and for the UK/AUS/NZ it is 230 volts.
Now, when the voltage deviates from this range such as during power surges weird things can happen. Voltage surges can be defended against by using surge protectors but I will go into more detail about those soon.
Firstly, let’s look at the fish tank filter circuit. The fish tank filter will be plugged into a wall socket. This wall socket could have failed as a result of voltage surges (especially if it had a bit of wear and tear to begin with).
The wall socket circuit will be protected by circuit breakers in the switchboard. These are typically MCBs and RCDs. MCBs protect the people and property from fires occurring. This is due to short circuits or overloads. This could be due to a short circuit with the fish tank filter.
RCDs protect people from a fatal electric shock occurring. It does this by automatically shutting off power when a certain current threshold is met. For example, if a fault with the fish tank filter occurred which could result in a shock, the RCD will trip within 30 milliamps of current and 30 milliseconds. Just enough to prevent long term or fatal harm from the shock.
Unfortunately, none of these breakers will protect the fish tank filter in the event of a voltage surge. These surges are common with power outages or lightning strikes.
For power surges, surge protectors are used. They work by diverting high voltage away from appliances and discharging it safely to the earthing system. This thereby protects any vulnerable appliances.
A surge protector is a good investment when you consider the cost of replacing several appliances such as microwaves, TVs and others which will be affected at the same time.
With this in mind, let’s look at the three things that can go wrong after a power outage.
Fish Tank Filter Not Working After A Power Outage? – Reason #1
Voltage Fluctuations
Likelihood: High – common in our experience. Contact the company which manages the local power lines for more information.
Fixable? Most likely not. It will need to be replaced.
Fish tank filters are designed to operate with steady voltages. When this changes components inside such as the motor and any electronics (if any) will get damaged. Capacitors in electric motors are especially susceptible.
These will short out if the voltage gets too high. Capacitors are used to help the motor inside the fish tank filter work. If electronics are present, many components on the board such as resistors, capacitors and semiconductors will be affected. In most cases it will make more sense to simply replace the fish tank filter.
Fish Tank Filter Not Working After A Power Outage? – Reason #2
Burnt Out Plug Socket
Likelihood: Moderate – especially if the outlet already has signs of wear and tear.
Fixable? Yes, the socket can be replaced. Plug the fish tank filter into a different plug socket in the meantime.
A burnt out plug sock is one reason why the fish tank filter isn’t working. Plugging the fish tank filter into a different plug socket can confirm if this is the case.
Signs of a fault plug socket are switches that feel different to press (compared to others around the house), black ash around the edges of the socket, or even weird fishy smells coming from the outlet.
Fish Tank Filter Not Working After A Power Outage? – Reason #3
Lost Incoming Electrical Feed
Likelihood: High – only if the property is on two or three phase power.
Fixable? Yes, wait for the power to come back on. Contact the local power lines company for more information about the fault.
If a property has two or three phase power it means that it is powered by two or three independent feeds. At any time, one feed could go offline resulting in partial power loss.
The same can occur after power outages where one feed comes back online but the other one stays offline. If the fish tank filter was on this offline feed it wouldn’t work for obvious reasons.
Plugging it into another outlet which works can resolve the problem. Waiting for the power to come back online will also fix the problem.
Electricians Perspective
A voltage fluctuation damaging key components inside the fish tank filter is a big potential reason why it isn’t working after an outage in my opinion. Also check for a faulty power outlet by plugging the fish tank filter into another outlet. If the property is on three phase power it might be possible that one phase is out. Waiting for it to come back online could fix the problem.
We Fix Faults is an electrician fault finding blog based on personal experience. If you have a specific electrical topic you’d like us to cover, send us a message above.