I decided recently to rescue 12 Betta's from my local walmart and petsmart. I was shocked at how terrible the Betta's are treated at walmart. They are all shoved way up under a dark shelf where no one can see them, and those little cups they come in were barely half full with water. I saw 2 dead Betta's, that had been dead at least 3 or 4 days, because the water looked like milk and the fish had started disintegrating. Really made me sad, and mad at the idiots who allow that to happen to the fish and never check on them. I took some of the Betta's to the sink and gave them more water. I am going to have a conversation with a manager about that soon.
Anyways, all of my 12 Betta's are in gallon sized bowls, tanks, and critter cages. They all have gravel and a small decoration or plant. A few of them have an LED light. But unfortunately, I don't have the funds to provide them with a heater or filter. But, I feel that I am giving them a much better life than they had in the pet store. They now have more water and swimming space and a plant or decoration to play in. Maybe one day I'll have the money to get bigger tanks with heaters and filters, but right now that is the best I can do for them.