Natural denitrifiers in nature

Hey, I get most of my stuff from the sea and stuff in Jamaica. I'm in the process of cycling my fishtank. I have a quick question. Couldn't I find some kind of substrate or rock or plant in the sea or mangrove or anything that would already have allot of denitrifying bacteria on it?

 

The 1st saltwater tank I set up was using sand from the gulf of Mexico- it worked fine. I am told each region has different microbes but they all do pretty much the same job .

 

Thats what is supposed to be so good about using L/r and sand Its for the bacteria not what living in and on it as 90%+ of the live animal life on it will die off anyways.. Now the bad stuff on and in it seems to not die off so easily unfortunately ):
I'll pass on to you what I have learned over the yrs about adding stuff to a marine aquarium.
The most needed and least added is Patience Give it the time now to come along slowly and mature and enjoy it for many yrs..And a lot less troubles and problems.. Thats just free advice and to some thats all its worth..

 

Take what you can LR/LS/NSW and then take more! You are very lucky to be where you are. The tank will be fine in no time

 

You shouldn't have any problem with taking live sand etc. from the caribbean where you are, just be careful not to get polluted etc. sand etc. from river run off or cruise ship ports, as you may encounter possible water/sand quality issues. Your best bet is to take a boat off shore and collect from reef areas there.
You don't know how lucky you are, living where you do, just be careful and use common sense!!!!!...Just my opinion.