I try to make sure its completely mixed and no particles are undisolved that
could contact anything in the tank. my 180 is very cramped and I've never
had any ill effects from anything in the tank. I pour it into this tank
just in front of one of my streams pumps (not into but just outside where
the flow is max), I do half on one side and half on the other, it blows
directly across the blue Acro I sent you the pic of that time and it's never
caused it to even retract a polyp. the flow on that Acro is so strong that
it grows in a curved pattern so it's getting pretty much a pH 12+ dose when
the slurry is added.

the spot where I add the slurry to my 29g is considerably lower flow then
the 6100's put out and it's directly above a Hydnopora Rigida (Horn Coral)
it as well never retracts. no fish ever show a change in repertory behavior
either.

while it's recommend that you do the slurry at night when the tank has it's
natural tendency to decline in pH I've done them during the middle of the
photo period as well. a 0.2 spike is the same IMO day or night and the
natural rise of pH due to photosynthesis isn't going to be so great as to
cause a problem with the spike.