Hey, glad I got ya!
Super that you haven't added any rock yet. Why? Well, here's what I would do; it saves money, the natural reefs in the oceans and it is awesome to "watch happen":
At any time (as in tomorrow, even - or whenever you can get it) I would get some dry lace/bowl rock. This is usually kept in large, dusty bins
under the lineup of tanks in some fish stores. It is dusty and dry (quite "dead" as you can imagine
) but you can get some
large pieces which form large, stable "caves" on your substrate. Now, you don't want to "cover" your whole sandbed (keep in mind with the rock that you want as much detritus to fall
on the sandbed and not simply clog up the rock pores so you continually need to be "basting" it off). But you can use the dry rock as your bottom base piece(s) and build on top of it. Advantages? You betcha! You won't have to worry about rockfalls as much because this is the most stable base you can naturally form without gluing rock together. It forms a natural cave for the fish(s) that take up residence. For a small tank, you might use one cave piece as your base. For larger tanks, you can use more - each one will normally only be "taken" by one fish. Or not. In our reef we've got it all set up like a 5* hotel, but both the yellow tang and the powder blue prefer "smaller" residences. In another tank? That cave is
owned by a clown trigger... but guess what? After learning that he was an endless chase for dinner with no yummy results, a blue damsel is no longer "always on the run" and shares the back portion of the cave with him (close to an exit hole, of course!
).
Point is, it may or may not be used (some fish actually like the
smallest nook they can fit in), but you can look "in" to these caves at any time, day or night, and see the epifaunal life literally "swarming" around.
Okay, that's the "foundation" part of your reef structure. Now? I absolutely recommend "forming" your live rock with as much as 80-85% additional rock pieces. Hey, "dead?" you might ask? Don't worry about it. Not "pretty?" Again, don't worry. I left about 15% unaccounted for, no? This you can seed with
premium live rock that you hand pick from your favorite lfs.
Why this "process?" The rock immediately begins accumulating all the same bacteria that would normally be populating any other "live" rock in the tank. It immediately provides the most important part - shelter. It also "makes" a reef.
But it's not purple and pretty! Again, don't
worry!
You know the "seed" rock? All that stuff
will spread to the "barren" rock. Within a year, you should not be able to tell a bit of difference - I mean that. There's not a person (myself included) that would be able to "sort" which rock in my tank came from the natural "reef" and which portion was actually "created" within the tank. Because of it's "lava-like" porous structure, some pieces of lace rock I know went it "dead" but that's the only way I have of knowing.
And when all is said and done you will have done a fine part in "saving" your otherwise chunked off portion of the natural reef along some beautiful coast. I'm the last person who's going to be labelled an "ecofreak," but I do like to be responsible and conscientious
on my own so I can tell the PETA folks where to go!
Seriously, though we should take whatever steps we can to be conscientious with
both rocks and fish/inverts we take as pets.
Also? It sure is
neat to watch your rock come alive with the spread of polyps and coraline algae. Super!
You will suffer not a single thing in the process, nor will you tank be any less "able" to perform as a sound biological filter. This is the only way we start up a new system. At first, the lure was the money we saved in buying hundreds of dollar's worth of rock. Now that I can't tell a difference after the tanks are established, it's not just the money saved, but the joy of watching an actual slice of reef "form" in your own tank.
Anyway, that's just my "take" on adding your rock. If you haven't added any "live sand" yet, sure - stir the sand again before you lay your rock down... won't hurt, helps accelerate the bacterial population. Also, as long as you feed the tank (to feed the bacteria to maintain the cycle started with the shrimp)
you should experience
no cycle "spike" with the addition of any few pieces of live rock you add to seed the base rock.
This is not
THE way. It is only my personal way. But not a person who has gone this route regrets it... Meaning, you are not being "shorted" in your goal of a beautiful reef. Some order 1lb/per premium live rock from a M/O company, and some "build" it piece by piece from handpicking the "best" pieces from lfs in the area. We've done both. But now we only "grow" our own. And you don't need to heed any pound-per-gallon "rule."
Just build enough to provide necessary "hiding spots" for any fish and enough to have places for coral attachment/growth. Sometimes it's nice to aesthetically build a formation you want - but you only need enough rock to do so. More important than excess rock is not "smothering" the surface of your DSB. That's your "spent/excess nutrient processing grounds," if you will.
So that's my take on it. You can build your rock at any point with the dry base rock, and as soon as your nitrates zero out you can slip in the seed live rock with no risk of creating any new mini-cycle. You may want to "seed" the DSB with a scoop of sand from your lfs at this point, as well. Enjoy the ride! I think it's absolutely awesome to "grow" your own slice of reef with a bit of "seed" and if I could, I'd be starting a tank every two months!
HTH!!