I'm sorry your new aquarium's not going so well. You may want to read over these pages on my web site:
http://www.fishpondinfo.com/betta.htmhttp://www.fishpondinfo.com/frog4.htmhttp://www.fishpondinfo.com/first.htmhttp://www.fishpondinfo.com/chem.htmhttp://www.fishpondinfo.com/health.htmetc.
What do you add to the water aside from "Aqua Plus"? Does the tank have any kind of filter or aeration? How much and how often do you change the water? I suggest doing 50% a week. It's hard on such a small tank. You can take one of the small "gravel vacuums" and pull off the wide tube end. Use the tubing to drain the tank water. First, you fill the tubing with water and hold both ends. Then, put one end in a bucket. Put the other end in the tank. Let go of the ends. It should drain out. Move the end of the tube along the floor to remove debris. I used to have a 3 gallon tank but it was so hard to clean that I put it up.
The white chalk stuff may have been columnaris which is actually a bacteria that can look like fungus. Antibiotics can help with that. Or, it could have been fungus.
My African dwarf frogs have never shown an interest in the frog bites which I put in anyway. Mine eat live blackworms. They should eat the frozen bloodworms but need some variety. I feed my fish twice a day, just a little bit each time.
I hope you have better luck now!