Guppies are often sold in a bowl. This has led to the idea that guppies can actually live in a bowl for a long period of time.
Yes, guppies can live in a bowl for a short amount of time. But you should not keep guppies in a bowl for a long amount of time. A fish bowl simply does not have the proper amount of surface area to allow for proper oxygen diffusion. Fish bowls are also usually too small for the amount of guppies you probably want to place in the bowl.
Why Bowls Are Bad For Guppies
As mentioned previously, fishbowls look great, but they really are not great for keeping your guppies alive. They just have too many problems with them. The only fish that fishbowl really work for are bettas, and even then you can do better than a fishbowl for your betta.
Anyway, this section will cover all the reasons that a fishbowl is a terrible idea for guppies.
Water Surface Area Is (Usually) Too Small
The first problem with having guppies in a bowl is that the water surface area is too small. For those that don’t know, water surface area is the amount of water in your aquarium that has contact with the air.
This number is obviously much smaller in a bowl than a standard aquarium. The reason is rather simple, too. Just look at a fish bowl and compare it to a normal aquarium. The fishbowl starts out small on the bottom, gets big in the middle, and gets smaller at the surface.
That means less room for the water at the top to contact the air, which means not enough oxygen diffusion in the tank.
This is critical because carbon dioxide will diffuse out the water through the surface. Less surface area means that carbon dioxide will build up in the tank.
Temperature Is Difficult To Control
Next, the temperature in a fishbowl is extremely difficult to control. Now, this is not because of the fishbowl itself.
It’s because 99% of fishbowls only hold a couple of gallons of water at the absolute most.
Good luck keeping 2.5 gallons of water at a constant temperature. Even the best water heaters will struggle to maintain a consistent water temperature with that amount of water.
Guppies are hardy fish, but having the temperature swing wildly from the daytime to the nighttime will stress them out. And stressed guppies have a tendency to lose their colors and get sick more often.
Fishbowls Are Too Small For Guppies
Yes, fishbowls are far too small for the amount of guppies you want to keep in it. The average fishbowl will hold 1-2.5 gallons of water.
Again, guppies are a very hardy fish, but you still should try to have 1 gallon of water for every 1 guppy at the minimum or else they could have problems like a bent spine. We recommend 2 gallons of waters per guppy for optimal guppy health.
Guppies May Jump Out Of The Bowl
Finally, guppies in a fishbowl without a lid may actually jump out of the bowl.
Yes, guppies do jump out of the water from time to time.
Of course, the guppy will not survive if it jumps out of the bowl unless you are there to drop it back in the water.
And no, putting a piece of cardboard over the bowl is an even worse idea as it greatly reduces the oxygen exchange at the surface. A mesh cover is much better, but most do not do that on a fishbowl because it looks ugly.
Can Guppy Fry Live In A Bowl?
The above section discussed keeping adult guppies in a bowl. This leads to the question about keeping guppy fry in a bowl.
It is not recommended to keep guppy fry in a bowl. However, they will fare much better than adult guppies in a fishbowl.
Fry are small enough that they produce basically no waste. The problem with keeping them in a fishbowl is more a problem of keeping the bowl clean and the right, stable temperature.
That said, if you can keep the fishbowl clean and at a stable temperature, then you can keep guppy fry in a bowl. Just don’t keep them with guppy fry with adult guppies in a fishbowl – the adults will eat the fry because the fry don’t have anywhere to hide!
Is A Filter Necessary For A Fishbowl?
No, a filter is not necessary for a fishbowl. You will just have to do a lot of water changes if you don’t have a filter.
The CO2 will build up fast in the fish bowl, which will result in a big algae problem. This can be somewhat mitigated by doing a 50% water change every other day.
That sounds like overkill, but it’s really not. Remember, a fishbowl will have anywhere from 0.5 to 2 gallons. A water change should only take 10 minutes to do with that amount of water.
Despite that, the best filtration system is having a lot of plants in your fishbowl. Plants will absorb the CO2 and other junk that builds up in the tank. A planted fishbowl also looks great.
Keeping Guppies In A Large Fishbowl
So, you really should not keep guppies in a fishbowl. The oxygen exchange at the surface just is not enough to maintain a healthy tank.
However, if you have a large enough fish bowl, then it is possible to keep guppies in a large bowl. Here are some tips for doing that.
- The fishbowl should be over 5 gallons.
- 1 or 2 guppies per gallon of water.
- Only male guppies in the fishbowl.
- Keep a lot of live plants in it – the plants will suck up the CO2 in the tank.
- Use a filter in the beginning.
- Use a water heater.
- 50% water change every other day until the plants are fully grown.
The above tips should keep a fishbowl in a good enough state for guppies to live in it. It’s not the ideal situation, but it will work.
The most important factor, in our opinion, is not overcrowding the tank. Keeping a lot of plants in the fishbowl also makes it much easier.
In fact, you don’t even need a filter to keep the fishbowl clean if you have enough plants in it. The more plants the better.