zero, sorry bud, but first of all it should be phrased," i dont want my animals to die off, not i want colour in my tank", putting it this way kinda makes u sound abit cold.which of course i know is not your intention!!
second, what is the species name of this yellow poylp? other will be able to input their experiences!
third, do u know how long they were housed at the
LFS and under what lighting conditions.?by now they should be on their way to blooming with proper
acclimation proccedures.
forth, did u have the space to quarentine these corals, or really check them for unwanted hitchhikers, a pest could be a cause for them to be regresssing rapidly?
4 days on the second addition u said!
fifth, it could be the length of the lighting period, personally i would not advise dropping the lighting time just yet, corals like all of us need energy to grow. in saying that, i dont know the species, or the distance u have the lighting set at, u have not mentioned that they look like they are burning/bleaching ect
sixth, what additives are u adding to the tank?
also you guys might keep ur temp higher than us, but its 2-3points highter than i would have mine
seventh, im going to stand aside now and let the community of your peers fill in the gaps
we will try to narrow it down for u ok, i do hope u can bring this under control soon bud!