My boss has had is tank up for 10 or 15 years but recently i talked him into getting a more colorful piece and it died instantly. it has xenia, regular brown zoaithid colonies and frags and another type of pulsing something or anothers the grow like weeds my question once something stays the exact same for this period of time do you think its so established it would be bad to change or what because he wants more color but every time we by a frag or anything it dies but the currnt stock thrives? puzzling realy