Rant alert: This is about the stupid things pet stores promote which aren't very nice to fish
This morning I went to Petco to get some new plants for my 36 gallon tank. Now normally I like my local Petco. They generally have nice fish and their tanks tend to be very clean and look better maintained than the local Petsmart. They also have some fairly knowledgeable people in the fish department...sometimes. Unfortunately, they also have a variety of the things I hate: fish tanks, especially betta tanks and "betta kits" that are WAY too small. Here is one I found today:
Now this is just mean. The water looked clean, so it had probably been changed quite recently, but still, there was only 2-4 cups of water in the whole "kit." That is way too little water for even one betta let alone two, and there is hardly any room to swim around in there, in fact, the fish were barely moving at all. There is a common saying that bettas like or need very small tanks. This is simply not true. They will survive for a while in small tanks because they are very hardy fish, but this does not mean they are happy or healthy. In a small tank, bowl, vase, or cup without a filter, the ammonia in the water builds up extremely quickly, which burns their gills and shortens their lives. Also, imagine living in a small jail cell with just enough room in it to turn around. Would you be happy? When I upgraded my betta tanks from 2.5 and 3 gallons to 5.5 gallon tanks, the fish became so much more active and happier looking. They are not super fast swimmers like Glofish, but they do swim around and explore the whole tank, including the small enclosures I provide them with in case they ever want to hide.
And speaking of Glofish, there is another species that is often mistreated. Have you ever seen those 2 or 3 gallon "Glofish kits?" The pictures on the front usually have a whole bunch of Glofish swimming around. This is very misleading. Gofish are genetically modified zebra danios, and just like danios, they need a 10 gallon tank minimum to have a basic school of 5 or 6 fish. Putting say, 15 fish in a 2-3 gallon tank will cause the same ammonia problems as keeping a betta fish in 2 cups of water.
So why do they even make all these little tanks and kits? BECAUSE THEY SELL. Having a tiny aquarium on your office desk seems like a great idea, and there are so many stylish and pretty looking kits that you can get for cheap, but it is cruel to the fish and NOT responsible fish keeping.
Please don't buy these betta jails. Just don't.