As for housing I think the bigger you can get in tank size the better. 4 or 5 gallons is ideal with little water movement. As for gravel and decor its up to you but some sand or gravel, a little cave to hide in and some soft silk plants that rise to the top is ideal. Lighting is up to you but you want to see your fishes lovely colours and make sure the tank is covered as they can jump. Get a thermometer and see what the temperature is as they like tropical temps. Anything between 24-30c. As long as its constant then they wont suffer much from bacterial problems.
They are the greediest fish for their size so you have to monitor food intake very carefully. Theres a whole load of foods available but try to get food meant for bettas. Pellets are good with a little bloodworm now and again.
Water is a bit of an issue as you have ammonia in your tap water. I think you can get dechlorinators that neutralise it i think but i dont think you should use bottled water as it has many minerals in it that may be poisonous.
If you cant find anything that neutralises the ammonia then its going to have to be the lesser of two evils and you may need to use bottled water. Find one with low salt in it.
Hope that helps