Today I went out and bought a better heater, and returned the crappy little betta starter kit I had bought. I also got a small water filter.
When I went back to Petco I found a bunch more of the baby bettas dead, and one on it's way out. It's really awful they are selling them this little. They have about 2x as many babies as adults in stock, and they don't seem to be selling well. Most of their little cups are so dirty and have green nasty on the bottom. I called the manager and asked if they clean and feed them, and she said only once a week! Everything I've read online indicates they need clean fresh water and frozen food way more frequently!
My little guy is doing 100% better already. He is swimming around, and being super active. When I put the filter and the new heater in he went over and explored them a bit, and then went back to his business.
I've read a lot online about the best way to care for him and here is what I've concluded.
*Get a heater and keep the tank at a stable temperature as close to 80 degrees as you can. My heater is supposed to keep it at 78 and that is the best one I could find small enough to fit this tank.
*Use a filter! Despite what people think, bettas like clean water as much as other fish. Just make sure your filter isn't too strong, as tiny baby bettas can easily be pushed around by a strong water flow.
*Feed your baby frozen brine shrimp! Also frozen blood worms, and daphnia are good, but I could only get the frozen brine shrimp. Don't feed him pellets yet!
*Only feed him a little bit! This might sound mean, but he will eat and eat until you stop feeding him. Apparently the amount of food should be about the size of his eyeball. I've been breaking it up so it's 3 times a day.
*Make sure there are plants (preferably live ones) in the tank. Mine little guy has been hanging out next to one of them on and off most of the day. He seems to really enjoy swimming through the leaves and stuff.
The Tetra Whisper 3i In-Tank Filter, and the Tetra HT10 50W Submersible Heater
Both in action!
You can see I got a little thermometer to make sure the tank doesn't get too hot or too cold.
Here he is hanging out next to his heater. He is sooooo tiny, but he seems much more healthy already.
The whole tank. Both plants are real. You can't see him, but he's in there somewhere.