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I think your fish list is okay for a 75gal. With those messy eaters in there you will need a pretty regular cleaning schedule so keeping the bioload down is a must to maintain acceptable water parameters.
is not needed in the begining. NH3
, Ph are whats important.
Do yo mean like a tap water conditioner? Skip it and use RO
water. A much higher quality water then regular tap and less likely to cause you problems. You can get it at most LFS
or just buy a RO
filter and make your own at home.
lots of live rock......so expensive
I suggest using sand instead of CC
. Easier to maintain.
"The Conscientious Marine Aquarist" by Robert Fenner.