Good evening,
I am starting a 55 gal aquarium this weekend. I wanted to ask a question and this may turn into a bunch of questions. So, I want to say thank you to everyone in advance. So far I have had nothing but great advice from this community.
Question 1 of probably a million lol!
1. If I setup the 55gal slowly with just mixing salt water, adding live sand, and adding a filter with no rock or anything else, will the tank cycle without the rock?
Straight forward answer, yes. Cycling is the term describing the growth of bacteria, enough to sustain life. Now straightforwardly, yes, your tank will cycle. You have sand in there, and bacteria will live in it. They will also live in your filter, and basically any surface possible.
Long answer though, there may not be enough bacteria to take on your tank - at least not easily.
There are ways around having to use live rock though. So long as you have biological filtration, then your tank can, and will cycle. This means that biological filter media such as bioballs or ceramic noodles, for example, are possible.
I would personally suggest Marine Pure, a product in the market that can sustain large, large, large amounts of bacteria. The biggest block you can get (it's sold in the forms of balls, tiles and blocks) is more than enough to filter your 55g, and it's actually only 8'x8'x4'.
There is an issue regardless though, if you add live rock later on.
Cycling is designed to produce enough bacteria to break down the general load of organic erm, stuff.
However, live rock can and do have die-off, sometimes more so than the current bacteria load can handle (even after cycling), which initiates another cycle. Depending on the amount of die-off, it can take a while, and depending on how much die-off there is, it can occur
each time you add live rock. Or rather, each time you add live rock, you can end up raising ammonia and stuff enough to kill your fish and corals.
So it's good to add your live rock in beforehand.
Of course, that doesn't mean there's no way around it. Most people use cured rock, which is basically cycled rock, to add to their tanks. Others use base rock, or 'not-live rock', which will not have any die-off.
And... yeah.
