Just to add a few more info about my plans;
After some research I decided to get two different species: Mandaçaia (Melipona Quadrifasciata) and Guaraipo (Melipona Bicolor).
The Mandaçaia is the first I´ll purchase and is just slightly smaller than the Apis Melifera, reaching about 11mm in length. It is probably the tamest of all Brazilian stingless bees and thus considered one of the best to keep at home. Their colonies are quite small, with about 600 to 700 bees, but nevertheless they can produce 2 to 3 liters of honey a year (up to 4 liters in special cases). They can also adapt to the region I live in, where temperature can go down to 5 degrees during winter. But they are not very hygienic, bringing some dust and other garbage to the hive, so the honey must be collected with some care to avoid contamination.
The Guaraipo is a little smaller, with about 9mm, and is also so tame that one can open the hives to extract honey with no special care or protection. They form bigger colonies than the Mandaçaia, with up to 1500 individuals, but the honey production per colony is smaller, about 1,5to 2 liters a year (up to 3 liters in particularly favorable conditions). By another hand they are more hygienic, not bringing too much trash to the hive. This species can also resist to moderately low temperature levels, about zero degrees Celsius, if the weather does not stay so cold for more than a day or two. But they cannot survive if the air is too dry, and some water reservoirs must be placed inside the hive if humidity goes too low.
These are the “girls” I intend to install in my balcony. I´m moving to the new apartment this weekend, and will start to build the hives as soon as I´m established in there. If everything goes well, I´ll order the first swarm in one or two months.
BR to all.