After researching a bunch of stuff on the forums here, I have compiled a list of what I have bought for my 5 gallon tank setup for my betta Cobalt. This is something that I thought would be a nice starting point for a person who doesn't know much about what to get, or who feels a bit overwhelmed about which items to purchase. I know I felt a bit confused when I realized all of the things to look for to make a happy betta, so hopefully this list will help you out!
So far this has been a nice tank. Though the lid plastic is a bit flimsy, it is certainly durable enough if you are careful when opening and closing the lid. For the price though, you can't beat it!
I have made this list on amazon.com, which is where I purchased the items:
Some notes on the list above:
The airline tubing is used for siphoning/gravel vacuuming. It takes about 20 minutes to siphon out 1 gallon with that size tube, but it's main advantage is putting clean water back into the tank. Since it takes a long time for the new water to go into the tank, it is less stressful on the betta. Plus if the tube was much larger you wouldn't have much time to vacuum out the gravel!
You may also want to buy a silk plant at the pet store when you go to pick up your betta. The middle silk plant in the attached picture is a plant I grabbed at petco. It adds some more hiding places too!
Also, I don't have the hammock added in the picture below (which is optional by the way), but is a nice addition to your betta's home!
The tank from walmart actually comes with a filter, so if you need to keep it cheap you could probably just use that. But since I want to cycle, I purchased the filter from amazon which comes with the sponge and has overall better reviews. Either way, some kind of filter is generally better than no fliter!
Anyways, hopefully this helps people looking to buy stuff for a new betta. If there are any questions or edits to this I should make just let me know!