I just purchased my first betta a few days ago, and bought a small bowl for him to live in, with a gravel floor and a silk plant from him to swim around. Compared to the tanks i have seen here, what i thought would be a good sized bowl for a single small fish looks rather small. Its huge compared to the plastic cell I bought him in, but its probably no bigger than one gallon or so. The problem is I'm living in an on campus apartment, and there really isn't a ton of area in my room where i could put a 3-5 gallon tank. How necessary is it to get a large tank for a single betta? Is it simple for them to have excess room for them to explore, or can a small bowl cause adverse health conditions for my new fish? I know a smaller bowl will mean more changes of water, but beyond that, is there anything I'm missing here?
A small bowl could also cause boredom and stress leading to tail biting or listlessness. Also most bowl shapes are hard to get a heater for let alone manage a temp in the quantity of water. Water quality is easier to maintain in a larger tank and is less harmful to the fish if you miss a water change by a day or so.
A 2.5 - 3 gallon tank however really isn't large at all. I have my Mini Bow 2.5 shoved on some extra counter space between a wall and a sink and it fits just fine. To be honest it's probably just taller and a little wider then the bowl you have now. c: If you go to a LPS you can see what I mean and with a lot you can just open the box to see the actual size.
You can also get like three gallon glass jars at walmart for cheap as well if you want to go that route and just keep it unfiltered [or get a sponge filter]. More room and easier to get a heater for as well =D
I've never subjected any of my fish, but I know from experience any animal kept confined to a space to small for them will suffer psychological problems. I work with puppy mill rescues and a lot of the older dogs even after they are removed from their small cages will continue to walk in circles because it's all they know how to do. At zoo's predator animals, like lions and tigers will pace the line of the cage.
I assume fish can do the same too. Sometimes I wonder if that's part of my one fish's neurotic problems. XD
Also not enough exercise can lead to obesity and we all know the affects obesity can cause on the body. :)
On the other note, they are limited to what space you give them and as Forbidden mentioned can become bored and start bad habbits that can be hard to break. I think a 2-2.5 gallon is a good amount of space. You can put a fair amount of things to occupy his attention with but have enough room to swim around and get exercise. You can buy a small 2.5 gallon rectangle tank at petsmart for $12 with nothing else that comes with it. It can easily fit on a bookshelf or desk without taking up to much space. I had 3 of them sitting on my desk for a while with plenty of room left.
We consider the absolute minimum to be 2 gallons--this is because bettas are tropical fish and need stable temperatures around 78-83 degrees. Most quality heaters are designed for use in tanks that are a minimum of 2 gallons in size. The other posters do bring up an excellent point--when any animal is restrained in a small area they risk developing neurotic behaviors such as glass surfing and tail biting. Obesity is a leading cause of death for these guys, so the exercise:feeding ratio must be taken into consideration where diet is concerned.
The biggest concern with small unfiltered tanks is maintenance. Fish constantly excrete a chemical called ammonia through their gills as they breathe--this is kind of like their form of urine. This ammonia is highly toxic even in very small quantities, but it can build up startlingly fast in small tanks. In nature, this ammonia would be broken down into less toxic compounds by specialized bacteria, consumed by plants, and diluted over a much larger quantity of water. Since none of these components are at work in your tank, you have to compensate by performing frequent 100% water changes. This is the only way to remove 100% of the ammonia and give your fish a consistently clean environment.
To give you an idea of how much work this entails, an unfiltered 2 gallon container would need a 100% change every 3-4 days, a 1 gallon would need one every other day, and containers of less than a gallon should be changed every single day. Larger, filtered tanks can undergo a process called the Nitrogen cycle, in which the bacteria I referenced earlier will colonize the filter and break down the ammonia into less toxic compounds--eliminating the need for 100% changes. Instead you would only need to do weekly partial changes which takes much less work.
You could always get a hexagon style 5 gallon tank with a filter--this tank is taller, but its footprint is actually very small. It likely would take up the exact same amount of space as your other tank. I have a Marineland Eclipse Hexagon style 5 gallon tank kit that is very practical for a small space--it comes with a filter and a fluorescent light that's ideal for growing live plants.
If you get a larger tank, you really will be doing yourself a big favor as well as your fish. Bettas can live for 5-7 years with proper care--so his home is going to determine your lifestyle for a long time. A larger tank will give you more leeway and a much more manageable maintenance regime.
Can you post a photo of the bowl he's in? The photo in your avatar is hard to tell, but it seems to be pretty small. The size of the bowl, will determine how often you need to do a water change. If it's TOO small, he'll need a water change almost daily, in order to maintain proper health.
Sound's like I'm gana definitely need a bigger tank. When i next get a chance to go get him some brine shrimp to fix the swim bladder problem he acquired while on the store shelf (poor fish), I'll look into a larger tank.
I went and got Ryu his new tank! This is it (if the picture works) Its 2 gallons, and has a thermometer and a filter. I'm going to keep an eye on the temperature, and if it drops to low, ill spring for a heater.
There are a few things to keep in mind with this tank--the thermometer you've chosen is going to be subject to a lot of different elements--the temperature of the room, the plastic on the tank, and the water in the tank. You're not going to get an exact reading on the temperature of the tank water with a stick-on thermometer, you'll just get a reading that represents how those different elements combine somewhere in the middle. If you want an accurate thermometer, you need to get the glass kind that actually sit in the tank water.
Another potential issue you may have with this tank is the small incandescent bulb in the hood. I had a tank very similar to this one when I was first starting out. I got a non-adjustable heater pad to go with it--the type that does not have a real thermostat. After a time, the fish developed an ich infestation despite my changing the water every 4 days. I soon figured out that the incandescent bulb was generating so much heat that whenever I turned it on and off I was subjecting the fish to rapid temperature fluctuations. The fish recovered, but he was never the same after that. I stopped using the tank and threw out all my non-adjustable heater pads at that point--you could always swap out the bulb for a fluorescent or simply leave the light turned off.
You should consider getting some silk plants that go from the bottom to the top of the tank--it's important for bettas to have areas of shelter at all levels of the tank and places to rest near the surface. Once you get some more decorations he should really start loving his tank.