Is a heater always necessary for tropical fish?

No, to answer your question. It depends on the species and your room's temperature. Often we think of tropical as hot but in reality, many tropical fishes in the tropics originate in cooler waters, especially during the rainy season. My fish room has a dehumidifier that puts out much heat during the winter months and keeps the room warm. I use two smaller wattage heaters in the tanks just in case. They rarely kick on.
 
One the biggest mistakes that people make is think that when we speak about tropical fish that it's neccesary to use a heater. Like Archerfish has already stated, it depends on the kind of fish we're talking about. The country of origin itself doesn't make afish tropical right away. It's the individual location where they occur in that particular tropical country whether a fish should be called tropical or subtropical.
But it's also the commercial trade which is responsible for the incorrect information that people just copy.
 
Not all, in fact many will be comfortable and thrive in what many consider room temperatures.

I'm in Canada, I only keep heaters on two of my tanks during the summer months (May to November), and the rest are flat out unplugged during the summer. And even then in winter the heaters are simply used as safety nets so temps don't dip too cold.

It heavily depends on your species though. If you're keeping things such as blue rams which need warmer, a heater might be necessary.




That being said, I'd like to touch on the topic of using a biorb, you will be heavily limited on what you can house in it. Even if, say, it's a 15 gal sphere type tank, you cannot keep much in it. Most fish require horizontal space to swim in and stake out territory. A sphere shape or bowl removes that. Plus, surface area is limited so oxygen levels are affected in these tanks. There isn't enough horizontal space regardless of volume of water they may hold.

Please factor this in, you may very well be limited to just a betta or even extremely tiny fish such as boraras depending on the overall length of the enclosure.
 
There are a couple of considerations.
Each fish species comes from a specific temperature, and around the equator, temperatures are fairly stable. That doesn't mean they are hot. When I was in Gabon, it was 26c every day. Water in sunshine was around that temperature. Under the forest canopy, it was a couple of degrees cooler.

If you look at a site like Seriously Fish, one of the good ones, it will give you the temperature range for each species. There's no one size fits all for tropical fish, as the tropics are vast regions.

The next question is your home. You're across the Bay of Fundy from me, and winter's coming. is the heat you keep the house at the heat the fish you want need? If no, you need a heater.
 
I'm starting from scratch with a biorb aquarium. Do all tropical fish need a heater?
Is there any chance you can get a normal shaped aquarium instead of a biorb?
Fish primarily swim left to right. Biorbs are not the best shape for fish and can be difficult to work out water volume if you need to treat them for anything. A standard rectangular aquarium is better for the fish and easier to work out water volumes.
 
You already have gotten the best advice… I’ll add, that I have a tank that I like to keep at around 70 degree F. ( and I live in Minnesota, and couldn’t live without air conditioning in the summer, and heat in the winter ) not being made of money, we are conservative on the thermostat… without a heater, the tank would eventually be room temperature…during the summer, the tank runs into the low to mid 70’s, and during the winter, down to the mid 60’s… so my heater runs a little during the winter… but I actually like having it, as most now tell the temperature of the tank, along with what the set point is… so I use mine as thermometers, as well as heaters
 
The previous comments are right on, so I won't deal with that aspect. I happen to keep many fish which live in weather in the 80sF. During the peak of the dry season their water can get over 90F. These fish are not happy in cooler water.

Of all the equipment we might use in a tank, the absolutely least reliable one is the heaters. I learned from two heater disasters where a heater got stuck full on. One wiped out an entire tank (120F) and the other most of the tank (104F). That was when I began using a heater controller on my most important tanks. I have never had a problem since with over heating.

I tend to use two smaller heaters in most tank rather than a single larger one. The smaller heaters always total more watts than a single bigger one I might use. This helps me to avoid single point failure being able to wipe out a tank. So I do not have a disaster from the water getting too cold.

For many years I set up tanks in what is essentially outdoors temperature-wise. To extend the amount of time I can have these tanks going I may have 15 to 20 wpg in them and always with 2 heaters. Early and late in the season the overnight temps get pretty low. I can handle down to 55F overnight and even an early single night drop as low as the high 40sF. But when things to be that cold overnight they tend to be pretty cool in the daytime as well. That is when the tanks must come down.
 
My Tilapia like high 80's in their grow out tanks ( outside ) the cubic shape of my tanks help maintain temperatures, during the hottest months of summer, & during the large temp swings of autumn... just before harvest time, we can have lows in the lower 40's ( even upper 30's ) , & highs in the mid 80's... I have 3 tanks hooked together in a system, but I use 3-4 heaters between the 3 tanks... my temps do fluctuate, between mid 70's at the coldest, to the heaters getting caught up, to the upper 80's, during the warmer temps of the day, on days with extreme temp changes
 
If your room can experience significant temperature change during a year. It's a good idea to have a heater to prevent excessive sudden drops in temperature. And keep it at temperature that mitigates temperature swings.

In countries that have large temperature variation during seasons, a heater is a must to prevent the water going too low in the winter.
 
The advice in the old days was even goldfish tanks can benefit from heaters if the aquarium itself is experiencing temp fluctuations including day to night. The idea isn't to increase the temp from it's normal high daily but to instead simply take any bounce out. Keep everything nice and consistent. Figure out the tanks daily high and set your heater there or close to it so the drops go away. I'm currently heating the entire store to 77 with the heat pump so any change from 77 and the buildings equipment adjusts the entire inside of the building and dehumidifies at the same time. I do plan to eventually go back and add heaters set to maybe 75 as a backup incase central fails which has happened a couple times during storms even though it's a new system maybe 5 years old now. Once was storm related, another was simply throwing a belt that they were able to replace.
 

Most reactions

Back
Top