New Tank & Cycling Questions

[worstist]

Hi this is my first saltwater tank but had freshwater tanks before.

REEF
Tank: 165G 66x24x24
Sump: 73G 48x22x16

100 LBS of BRS Reef Saver Rock
Added Dr Tim's Nitrifying Bacteria
Fishless Cycle w/ Ammonia
Pure RO Water w/ Instant Ocean

Day 1: Added to 3 PPM Ammonia w/ Periodic dose 1 PPM dose every 4-5 Days after Week 2.

PH Steady throughout.
No ammonia tested after Day 7.
Trace nitrite showed up Day 7, Trace nitrate showed up Day 9.
Nitrite was over ranged from Day 10 - Day 25.
Nitrate reached its peak of my test kit on Day 25 160+ PPM.

The only confusing thing I have was...
I tested on Day 27, my nitrite dropped to zero which is normal. But, I haven't read anywhere that the nitrate will drop drastically as well. I tested multiple times and it was only 20 PPM.

Never read about this before, anyone can chime in on this?



Also, I'm going to wait a week before adding any fish into my tank. I was thinking of adding some green chromis (7-8) but read about aggression issues, but will I have a better chance of them surviving because of a big tank?

or

I add a couple clownfish and maybe a blenny first. I am worried that I fishless cycled and built a high amount of bacteria. Will only adding a few fish have a negative effect on the bacteria? decrease population. Maybe I should add more?

Thanks, hopefully you can understand what I'm trying to ask.