My 4 year old received a Betta fish for her birthday from a friend. We were surprised she got a pet with no advanced warning. I'm trying to do everything right, and was interested in the type of plant you can put in their tank to help keep them healthy. "Twinkle" is just in a bowl, no filter or heater. We clean the water once a week, and so far have managed to not put her fish into shock. We got Twinkle on July 10th, and I hope to have him a long time!!! Please help with advise on how to keep Twinkle happy in his fishy bowl. My daughter will appreciate the effort!