at the moment i have a mix of differant corals but some are growing into other corals areas i know that corals attack eachother and can kill eachother off but do all corals do this? if so i will have to arrange all my tank which will be a nightmare with the aquascape i have.and i have a toadstool attached to a large piece of lava rock which i want to get rid of how can i seperate them?

not every coral kills others. Xenia, for example, is relatively harmless to other corals. Most agressive corals are hard corals. Corals are generally easy to detach with something flat and thin like a putty knife. This doesnt make the coral too happy, but it will be fine in a few days.

its always a good idea to google up whatever coral you have and check its agression tendencies. In general, hard corals have sweeper tenticles that can be several inches long and will come out at night and can sting neighbours. Most soft corals resort to chemical warfare, but good circulation can help minimize that. Still, several inches of separation is good as corals will inevitably spread out anyway.