As summer rolls around into full swing, you might find yourself wondering if you need something to help keep your axolotl cool. They come from cooler waters and thrive in temperatures most tropical fish can’t handle, but too much heat in the tank can be fatal for your pet.
Ideal temperatures for axolotls are between the cool 60s to low 70s. You don’t want to let the water in the tank reach above 74 degrees because this can stress your axie, cause health problems, and if the temp stays too warm, it could prove fatal.
Not everyone will need an aquarium chiller, but if you do, it’s important to figure out how much cooling you need, what kind of chiller will work best for you and your axie, and what will work for your budget. Here in this guide, we go over everything you need to know about aquarium chillers.
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The Lowly (Axo)lotl
Since 1935 axolotls have been in American labs, and soon after that they started showing up in home aquariums. Now there are many more captive axies than left in the wild.
Because of habitat loss, overfishing, pollution, and the introduction of invasive species such as tilapia—who multiply rapidly and routinely feed on axolotls—these fascinating little amphibians are nearly extinct in the wild.
They only exist in one place in the wild, in small canals in a small district in Mexico City, Mexico.
The water in their natural habitat is cooler than most tropical regions, so when you have an axie as a pet, you will have to keep the water in the tank cooler than most aquariums.
Do You Need a Water Chiller?
If your tank is set up in a room or an area that stays naturally cool all year round you may not have to take any special steps to keep the temperature in the comfort range for your pet.
Most rooms have windows though and have fluctuating temperatures. If the latter is the case, you will probably need a device to keep the axie’s environment cool and avoid potentially dangerous temperature fluctuations.
Another consideration to take into account is if you’re like me, you like to try and save energy by adjusting the thermostat when you leave the house for work. In the summer a lot of us set the temperature to a warmer setting so we aren’t wasting electricity cooling a house that no one is in for a large portion of the day.
In the winter, this may not be a problem because we typically set the thermostat to a cooler temperature while we are away. Having a water chiller set up in your axie’s tank will offset these temperature fluctuations.
Other considerations that can affect the temperature of your axie’s home can be the lights on the tank. If you are using incandescent lights or halogens, these types of lights create a lot of heat which can increase the water temperature.
Axies actually don’t need a bright light as they have no eyelids, are sensitive to bright light, and prefer low light settings. LED lights are best for this application as they don’t produce much heat and can often be dimmed.
Windows in the room can also affect the temperature of an aquarium. Depending on how much sunlight streams through and if the light hits the tank directly, the light from outside can increase the water temperature in a tank, sometimes several degrees.
While not everyone will need an aquarium chiller, if you find it difficult to keep the tank in the cool comfortable zone for your axie, you might want to think about investing in one. If the water your axolotl lives in stays too warm it could suffer and not live a long healthy life.
Use a thermometer to determine the temperature of the water in the tank, and then determine if you need an aquarium chiller. Below we will discuss the different types of aquarium chillers, the pros and cons of each, and what setups they work best for.
Different Aquarium Chillers and How They Work
Depending on the size of your tank(s), the amount of heat you need to remove from the aquarium, and how warm the room is will determine what kind of aquarium chiller you will need.
There are different types of chillers as well. There are probe chillers, inline, submerged coil chillers, and fan-type evaporative chillers.
Each has a specific way of cooling the water and may need additional equipment or require extensive setup.
1. Probe or Nano Chiller
These are chillers that work best for 10 to 20-gallon aquariums. They can work marginally well for tanks up to 30 gallons, though some are rated for 40 gallons. In a larger 40-gallon tank a probe chiller will only reduce the water temperature by about 1 to 2 degrees.
For larger applications, you can use two probe chillers on one tank, but more than two are not recommended.
These units work by using a probe inside the aquarium to cool the water that comes in contact with it while exhausting warm air out the back of the unit. As long as these units are plugged in they will continue to cool the aquarium water.
It can be difficult to maintain desired water temperature because there is no thermostat or automatic shut-off. You will have to monitor the water temp for your tank and plug it into a timer so that it doesn’t cool the tank too much.
These are one of the less expensive types of chillers on the market, but they require owners to drill a hole into the aquarium where the probe will insert into the tank.
They have rubber gaskets that attach around the probe but drilling glass can be difficult. Acrylic aquariums are recommended for probe chillers because the drilling process is easier with these types.
These probe chillers can also be suspended above the tank to where only the probe is submerged. The setup can be bulky looking and could ruin the cooler and harm the inhabitants if the unit falls into the water.
2. Inline Chiller
These types of water chillers are the most popular and have the widest variety of options for different tanks. These pump warm aquarium water into the unit—either they have a pump built in or you will have to use a separate device—cool the water and send it back into the tank.
They set off to the side of your aquarium and feed water through the unit to cool your tanks. Most of these works automatically and will turn themselves off when the aquarium water reaches the desired temperature you have set on the chiller.
These work much like air conditioners work and will exhaust warm air into the room so they will need room away from the aquarium so that it doesn’t work against itself. You will need to make sure the room isn’t closed off and gets plenty of airflows.
These units work great to keep the water at the perfect temperature for your cold water-loving axolotl. You can basically set these units up, turn them on to the temperature you want then forget about them. The problem with all of that convenience is the price tag, they can get pretty hefty.
3. Submerged Coil Chiller
These units don’t need an extra pump to keep the water cool. They take characteristics from inline and probe chillers, but they don’t need extra equipment to run, nor do they need to go through the glass.
Submerged coil chillers do just as the name suggests, the cold coil goes directly into the water to keep the tank cool, and like inline chillers, they have a thermostat and turn themselves off when the water reaches the set temp.
These are great if you don’t have room for an extra pump inside or on the outside of your aquarium.
4. Fans or Evaporative Chillers
Fans are the budget chillers as they can be the least expensive cooling units to purchase. They also don’t cool as well as refrigerant coolers because they rely on the cooling effects of evaporation to keep the tanks cool.
They usually attach to the top of the tank and blow directly onto the water surface. If you only need to cool the tank by a few degrees, don’t have the budget for a larger tank chiller, or you simply don’t have the space for more equipment, a fan chiller might be best for you.
If the room is unusually hot, an evaporative fan chiller won’t do much to cool the water.
Another negative about aquarium fans is they can be noisier than their refrigerant cousins. Depending on if you have two, four, or more fans, the noise can be a bit distracting at times.
They run constantly too, so you might have to put them on a timer if you need peace from the constant drone.
How Aquarium Chillers Work
Probe chillers work based on Peltier’s Effect in which voltage is applied to a conductor made of two different materials. One side heats up while the opposite end gets cold. The same principle is applied to units like wine coolers.
These do not get as cold as refrigerant coolers but work for smaller areas that don’t need to be very cold.
Refrigerant coolers like the submerged coil and inline coolers work by using a refrigerant that gets very cold. The same way air conditioners and refrigerators/freezers work.
With inline coolers, warm aquarium water is pumped into a heat exchange where it flows around very cold metal coils. The heat is transferred from the aquarium water and vented out as warm exhaust.
The refrigerant is cycled through the system where it is constantly heated into a gaseous form, then condensed into a liquid form. When it is condensed the liquid gets very cold, this is where the water flows around the coils to cool off the warm water.
As the refrigerant expands into a gaseous form it heats up. Air is blown over the condenser to cool it off. The expelled heat is then vented out of the cooler as an exhaust. That’s why these types of coolers need room for the warm exhaust to flow away from the aquarium.
Fan coolers work with evaporation. Much like the way sweat cools us when we step in front of a fan or a light breeze washes over us. Fans wash over the surface of the aquarium to evaporate the water which in turn cools the tank, but only a little bit.
An efficient cooling fan will only drop the temperature on an axolotl tank by one to two degrees. They work alright in rooms that are already cool, but not so well if the room is quite warm.
Best Aquarium Chillers for Your Axie
This probe chiller is a budget-friendly option for those with smaller axolotl tanks that only need to drop the temperature by 5 to 10 degrees.
If you have a 20-gallon tank this probe chiller may reduce the water temperature by 2 to 4 degrees. For tanks larger than 20 gallons, we would suggest getting a different type of aquarium chiller such as an inline or submerged coil.
The IceProbe comes with everything you need, no need to buy tubing or pumps, though you will need the tools to install it.
This probe chiller is a nearly silent cooler, so you won’t have to worry about noise. It does not have a thermostat or shut-off switch so you may have to set it on a timer or a separate temp controller to keep your tank at a constant temperature.
This big inline aquarium chiller comes with everything you need to start cooling off your aquarium up to 42 gallons. It comes complete with the pump and tubing, so you won’t have to purchase more equipment before you get started.
The Baoshishan will quickly drop the temperature in your axie’s tank by 8 to 10 degrees. It has a built-in thermostat and LED temperature display.
The titanium coils will last a long time under the stresses of aquarium water and keep the water super chilled.
For smaller setups, this 16-gallon chiller has an option most don’t come with, it can alternately cool and heat the aquarium water to keep the environment within the ideal range.
It comes with the pump and hoses needed to start up and go. You will only need to cut the tube in half before installation.
The Poafamx is vented on all sides for quick heat dissipation and efficient cooling.
For quiet operation, no pumps, simple plug-and-go uses, and a long, five-year warranty, look no further than the TradeWind drop-in chiller.
All you have to do is plug it in, drop in the titanium coil and let it start cooling off the aquarium. It will quickly and effortlessly keep the temperature as low as 65 degrees on larger tanks.
This chiller is best for tanks between 100 to 200 gallons.
The JBJ Arctica is one of the quietest and most efficient chillers out there. You’ll probably forget it’s even there.
As the name suggests, the heat exchange coils are made of corrosion and rust-resistant titanium that will probably outlast the machine.
This brand of aquarium chiller comes in many different sizes, from a small 1/15 hp all the way up to the commercial aquarium size of 2 hp. To put those numbers into perspective, the 1/10 horsepower chiller is rated to handle aquariums up to 200 gallons.
This unit also has titanium coils in its heat exchanger, but it also has a built-in surge protection feature.
You don’t have to purchase an extra surge protection cord to protect this chiller. It also features a memory recall for when it’s turned back on.
Another unique property this chiller employs is it has a freeze protection feature. Sometimes, if a chiller runs for an extended period, the coils can get so cold that they condense the air around it to the point the coils become a solid block of ice. The Hamilton Technology Euro Max has a built-in feature that prevents that problem.
This inline chiller does not come with a pump or tubing of its own, so you will have to purchase those separately. A word on pumps while we are on the subject, you will have to make sure you have the correct flow pump for the unit.
You will need a pump that is strong enough to send the water out of the aquarium, into the chiller, and back into the aquarium, sometimes on a vertical plane over 2 or 3 feet high. Make sure you have a pump that is rated with enough gallons per hour (GPH).
A pump that is too weak won’t be able to cool the aquarium and will end up burning itself out.
Hamilton Technology has chiller sizes from 1/10 hp, 1/4, to 1/2 hp. For maintenance purposes, this chiller also has a front panel that is easy to remove so you can quickly and easily clean off the dust and dirt that will accumulate inside the unit.
This quick-installing aquarium fan is as simple as you can get. All you have to do is set the suction cup onto the outside of the tank, and then adjust the airflow so that it is blowing across the surface of the aquarium.
This fan works best on smaller tanks—10 to 20 gallons. It is easy on the budget, but it can be noisy. If you only need to cool your axie by a few degrees, this may be the item you need.
Another fan option that simply attaches to the top rim of the tank and blows onto the surface of the water is this NINEFOX fan.
It comes in 2, 3, or 4, fan sizes for varying tank sizes and cooling needs. You can adjust the fan heads to blow straight down or tilt them to blow across the surface. It also has two speeds.
This budget fan cooler clamps on tight and will work for tanks that only need a few degrees of heat dissipation.
Here is a quick video that shows you how to install most inline aquarium chillers:
Potential Problems With Chillers
With all technology, you may encounter problems with the operation of some of these units. Below are some of the most common problems reported with these aquarium chillers.
Noise is a big complaint by many users, especially when it comes to fans. We all know box fans or oscillating fans can be noisy during operation, but even the tiny fans that blow across the aquarium water can be particularly noisy.
Though most of the inline, and compressor unit coolers have gotten much quieter over the years with the advent of better technology, some of them can still be rather annoying.
Refrigerant loss is another common problem. Just like any air conditioning unit whether it’s your car or your house, they all eventually lose refrigerant. When the refrigerant inside leeches out the unit is unable to cool as efficiently and may have to run harder to keep the water cool.
It may even quit cooling all together. When this happens to you, there may not be many options to fix the problem because aquarium chillers usually don’t come with charging ports. You can possibly have a welder add a refrigerant port to the unit, or you’ll have to replace the chiller with another one.
Refrigerant chillers can warm up a small room. They have to exhaust the warm air that’s created, and if it’s not ducted out a window then the warm air stays inside the room.
In larger rooms or areas that are well-ventilated, this is not a problem because the heat will dissipate through the air.
Increased energy costs. Depending on which type of cooler you use, and how big it is, your power bill will increase. For an average size aquarium chiller running 24 hours a day, you could see an increase of $20 to $40 a month.
Dust and clogged vents. Most of these units have fans that blow across the condenser units to help cool them off. With all that airflow, dust and dirt can get stuck on the vents, obstructing airflow, which in turn reduces economy and can cause secondary issues.
You will have to periodically clean these vents off by vacuuming the dust. If the dust gets too thick, you might have to clean the inside of the fins. This can usually be done by taking off the housing and using compressed air or a soft brush while vacuuming the delicate fins.
Always consult the owner’s manual and manufacturer’s recommendations before working on your units though. Working on the units yourself could potentially void warranties on the products.
Calcium buildup. As water constantly flows through pumps, hoses, and the heat exchange in the inline aquarium chillers it can restrict the flow. This will drastically reduce the cooling efficiency of the unit.
To clean the calcium buildup, you’ll have to regularly flush the heat exchange with a vinegar and water mixture.
Pump failure can stop everything from working. While this doesn’t happen often, the main way to prevent pump failure is to not let the pump or chiller run without water.
The heat buildup and friction caused by running dry can quickly shorten the life of the pump.
When looking to purchase an aquarium chiller, it’s better to consider how much heat needs to be removed from the entire tank, rather than how much water is being circulated. For example, a chiller rated to cool a 40-gallon tank will easily circulate the water but if it is very hot, then the unit will be working much harder to get to the desired temperature.
An aquarium chiller that works exceptionally hard to bring hot water down to a cooler temperature will not last as long. If the water is cool already and only needs to be chilled a few degrees, then the 40-gallon unit will work very well and last a long time.
Basically, what we are saying is, that you might want to get the next larger-sized cooler than the manufacturer recommends if you have a hot room or have to cool the water several degrees.
Another thing to consider is the lifespan of an aquarium chiller. Axolotls can live up to 10 to 15 years. Will your aquarium chiller last as long as your axie?
The short answer is probably not. The average lifespan of a refrigerant chiller is about 4 years. Some do last upwards of 10 years, but those seem to be the exception.
To help them last longer, periodic maintenance needs to be completed such as vacuuming out dust and debris, flushing out the pump and heat exchange to remove calcium buildup, and keeping them from overworking themselves.
Whether you use a probe, inline, or submersible coil chiller, you will need to make sure they have at least 6” of clearance away from walls and other obstructions. This is so the chillers can “breathe.”
Fans blow air across the compressors and heat-creating parts and need to have plenty of room to dissipate the heat. If there is not enough room for them, they can end up overworking, or not working as efficiently.
Pumps need to be considered as well. Some aquarium chillers have built-in pumps, some have submersibles, and some have pumps that work outside the unit and aquarium. You may have to create space for the pump, or if you really don’t want it sitting outside, you can get a separate submersible to go inside.
While we are talking about pumps and airflow, you still have to be careful to not have too strong of a current inside the tank. Axolotls are very sensitive, and their skin can be damaged easily. A strong current can knock your axolotl around or cause him stress because he has to fight against it all the time.
If the flow from the pump is quite strong, you might have to get a flow restrictor/diverter that helps to spread out the current so that it’s not causing pain and stress to your axie.
You might want to consider the added electricity cost of running a chiller and possibly a new pump. If your axolotls are staying pretty cool without any added equipment, then you can probably keep doing what you have been.
On the other hand, if you have been keeping your house at a chilly 65 degrees all year long to keep the water temperature on the cooler side for your pets, then you might want to seriously consider getting an aquarium chiller. The initial cost might be a chunk out of the wallet, but it could save you money in the long run.
What Kind of Chiller Do You Need?
Before going out and getting the biggest, ice-cold aquarium chiller that’s available because you want the absolute best for your pets, take a look at your cooling needs. Do you need a big inline unit because it’s scorching during the summer, or do you only need to drop the temp a few degrees to hit that axolotl sweet spot?
Understanding your axolotl’s needs will help you to find the right water cooler for your needs.
Is your house naturally cool?
Do you keep your thermostat around 68 degrees all year long or do you live in an area that’s generally cool? Are you able to open windows and let the natural refreshing breeze in?
If your house is always on the cool side, you may only need a fan for your axolotl to drop the temperature a few degrees. A big, heavy-duty inline chiller could be too much for your needs.
Do you suffer through scorching summers?
Is your house routinely hotter than the fires of hades? If you are having a hard time just keeping your axolotl tank in the 70s then you should get a more aggressive water chiller. An inline or submersible coil chiller would work best in this situation.
Is the room very hot or cold?
A naturally dark and cold room, say like in a basement, is probably the perfect environment for an axolotl, and you may not need any extra cooling at all. Simply check with a thermometer because if the water stays around 60 to 70 degrees, you won’t need any supplemental cooling.
A hot room on the other hand will need something to keep the water in the tank comfortable for your axolotl.
Are there a lot of windows?
Windows are great, but too much light and heat from the sun can quickly warm up an aquarium. If your axolotl’s room has a lot of windows or windows that let the sun shine directly on your tank, you will need some additional cooling.
How big is your tank?
As we have seen, smaller tanks can benefit from smaller aquarium chillers like the probe chiller, or a small inline. Larger tanks will inevitably take longer and more power to cool them to the proper temps.
How much cooling do you need? Depending on the ambient temperature around the tank you may need more or less cooling. Keeping track of water temperatures throughout different times of the day will let you know what kind of cooling you will need.
Can I use ice cubes to cool my axolotl tank?
A: You can use ice cubes in a pinch but there are considerations to think about. Make sure it’s non-chlorinated water and be careful of adding too much ice. You don’t want to shock your axolotl or other organisms that are in the tank.
What happens if an axolotl gets too cold?
A: Depending on how cold it gets an axolotl could slow down at temperatures in the 40s or 50s, its metabolism will slow down, and it may end up getting sick if left at these temperatures for too long. If an axolotl is subjected to temperatures in the 40s for a few weeks, it could prove fatal for it. Freezing temperatures can also be fatal for axies.
Are aquarium chillers necessary?
A: Axolotl’s need temperatures between the 60s and low 70s. Over 74 degrees Fahrenheit can stress the axolotl and eventually lead to its demise. Most axolotl tanks and setups won’t need a chiller, but if temps stay too warm, then an aquarium chiller is recommended for axolotl health.
Let’s Wrap This Up
Axolotls are watery pets that need a cooler environment because their natural habitat is fed by cool mountain water. This can be attained in many different ways, but the most effective and streamlined method is by using an aquarium chiller.
Depending on how much cooling you need, the size, and location of your tank, as well as other factors will determine if you need a chiller and what type will work best for you.
For light cooling of only a few degrees an evaporative fan cooler could work fine for you and your axolotl. Depending on if you have a need for more drastic cooling, you may have to look into a more aggressive cooler like an inline or submersible coil cooler to keep your axolotl healthy.
We hope this guide has helped you make your decision a little easier.