That depends on the size of your aquarium. Don't put more than one for every nine square inches of aquarium space. Watch their health closely. They let out dangerous toxins when they die.
This depends on the size of the tank. It is suggested that one anemone for every 9 square inches of space is good. However, make sure you watch them closely.
Depending on what size tank you have determines that amount of anemones it can house. The less anemones the better since they create excess nitrates which can dirty the water.
Depends on the size. Both on the anemone and the tank. 50 gal. per anemone should be fine assuming a medium size critter. Make sure the ones you have in the tank is compatible with each other as well as the current fish and coral.
Different specie, Different environmental factors requirement. If all the anemones are of the same type/specie, you may host as much as possible as long as you can keep them healthy.
