Growing soft corals in a saltwater aquarium is definitely simpler than growing hard corals. Soft corals are a lot less fussy which makes them low maintenance and perfect for beginners to saltwater tanks.
The reason they are called ‘soft’ corals is that they do not have a stoney skeleton like hard corals do. The fact that hard corals have an stoney skeleton means that they are voracious calcium consumers. That, along with stronger lighting, is what makes them trickier to keep than soft corals.
Soft corals should be placed far enough from each other, allowing them room to grow. Soft corals don’t sting as LPS do, but they do excrete a type of poison to prevent other corals from getting too close. This poison does not affect people, but is more of a warning to other corals.
The exception to the poison rule is that excreted from Palythoa coral. This soft coral kept by many enthusiasts needs to be treated with respect. While in the water they are safe, but when removed from water they are capable of releasing Palytoxin.
Incidents of Palytoxin poisoning have been in the news over the years when uninformed aquarists decide to clean their rocks, or cut or boil them (never boil live rock!). This toxin is capable of killing an entire family living in a house if Palytoxin is released into the air.