Anenome questions

Hey guys, I have this 20 gallon tank and I've always wanted an anemone tank, maybe throw in a couple of clowns. I have one RBT in my 90 right now but I'd like to have maybe 4 or 5 in a single tank. My thought is that I could setup that 20 as a little nano... add sand, rock, etc... How many anemone do you think a 20 could or "should" support and with that said, I'd like to split the RBT I have. is there a "safe" reliable way to "stress" the anemone to split. I could isolate the RBT in my quarantine tank and play with the water there so nothing else would be effected. Any suggestions, video's to watch, idea's all welcome... thanks in advance!