Saltwater aquariums are one of the many branches within the fishkeeping hobby. Most of the animals kept in these types of fish tanks do best in water temperatures ranging between 72°F and 80°F. You could be even more specific and say that they will do best in water temperatures between 76°F and 78°F. Although a lot of aquarium equipment gives off heat, reaching the appropriate temperature is often impossible without the assistance of something like an aquarium heater.
Another thing that heaters provide is stability in water temperature, which is important to keeping a successful aquarium. In the oceans, temperatures can swing quickly for short periods. However, we are not working in the ocean, instead we are keeping an ecosystem in a glass box, and want to provide the best for the inhabitants. Small swings in temperature will probably occur in your fish tank, but we are trying to avoid that. Stable water temperatures will help lower the amount of stress brought on your fish, coral, and invertebrates.
So yes, generally you will want to provide your saltwater aquarium with a heater. There are of course exceptions to the rule, which will be covered in this article but I recommend keeping a heater running on your saltwater fish tank. If you’re looking for ideas on which heater may work best for you, check out 6 Best Aquarium Heaters for Freshwater & Saltwater Fish Tanks.
Disclaimer for Heaters
Unfortunately, heaters are not picture-perfect pieces of equipment. They use large amounts of electricity in short bursts to warm your fish tank. Because of this, heaters are prone to being equipment that is likely to break, compared to other equipment. If you put your hand in your aquarium and feel a shock, it’s likely the heater is the culprit. If you feel a shock from your aquarium, it’s very important to remove the source of that electrical current. Take a look at How to Check For and Remove Electrical Current in a Fish Tank for information on the subject.
There are two things I recommend purchasing to help protect yourself and your fish from a potentially faulty aquarium heater. First, I would recommend purchasing a Titanium Grounding Probe. This probe is made to “send” electrical current out of your aquarium, which will help protect you and your fish. You can purchase the Rio RV2735 Titanium Grounding Probe or if you have 2 aquariums, consider getting Encompass Titanium Grounding Probe (2-Pack).
Your heater can malfunction in a way that it turns on and never turns back off. This can cause catastrophic damage to your aquarium by cooking whatever is inside. A great way to protect yourself from this is with the Inkbird Aquarium Heater Probe. This probe has a built-in over-temperature sensor fault alarm. This is an additional way to protect your aquarium from a potentially faulty heater.
If you’re in the market for a new heater, check out the Innovative Marine Helio PTC Smart Heater. It’s a little pricey but could be well worth the investment. It comes with a smart controller, temperature sensors, an alarm when temperatures get a little too high, and a boatload of other features.
Exceptions to Requiring a Heater
There are only two reasons I could see someone not needing to run a heater on their saltwater aquarium. Both situations are not very common but I wanted to state them regardless. First, if you keep your home anywhere between 76°F and 80°F continuously, you probably do not need an aquarium heater. Many of us live in climates with swinging temperatures which prevents us from doing this. One could still be kept in the aquarium as a fail safe, incase the home temperature ever dropped to lower temperature, but that’s completely up to you.
Also, if you enter the world of cold-water marine fish, you will not be using an aquarium heater. Instead, you’ll likely have to set up a chiller on your fish tank to maintain the proper temperature for those species of fish. These two scenarios are few and far between, but they do occur.
Final Notes
Saltwater aquariums can get very expensive. It’s best to create habits to lower the risk of your investment and to provide a great environment for the fish, coral, and invertebrates you choose to add to your aquarium. A heater is a fantastic way to raise your aquarium’s temperature and keep it at a stable level. Unfortunately, they are known to malfunction, but that’s why we have tools to lower the risk and danger when that does happen. If you have a heater set up that works great for you, please let me know! I love to learn from fish keeper’s personal experiences.