Life Rock vs Live Rock

Cmatthewsdmd · Nov 28, 2019

I am a 2nd time new aquarium owner. Last saltwater tank was a 90G 15+ years ago and let me tell anyone new that it was a different world then! My question is about volume of live rocks. My previous build I used 100% live rock from Fiji I believe , which is obviously one of the big changes since then. I just purchased about 40lbs of aquacultured primo rock from liverocknreef.com and I have been happy with the product and certainly surprised by the ease of getting it ready for the aquarium vs something that traveled the world! It has just about completed its initial cycle. I have a Read Sea Reefer 250 so I think I need another 60lbs or so of rock. I like the “live” aspect of the live rock and the potential for hitchhikers so I was thinking of going 60 more primo, but looking at it, the rock seems dense, meaning even 60lbs would not be as much volume as I may want.

my questions are:

How dense is something like life rock? Would it take up a bit more space or do I need another 80 either way?

I know many people start without any live rock or maybe just a little, but if I add life rock now instead of the live, what would be that advantages/disadvantages outside of cost?

the aquacultured rock seems a bit more base rock in appearance. Would life rock have a more visually appealing structure? Or is it similar?

thanks for any input!

chad

Euphyllia97 · Nov 29, 2019

1) Density of you rock will depend completely on the individual rock. I would suggest you to use the 40 lbs you have and let it run in the tank for a bit. Instead of buying more live rock, you could go for some man-made rocks like “Revoreef 3DM rock“ or “Real reef rock”. These are designed to be very low-density so that a lot of area for bacteria growth is provided.
Whatever type of dry rock you add to the tank will become ”live rock” anyway.

2) a) Advantages of using live rock:
Contains a lot of benificial bacteria and speeds up initial tank cycle.
Contains some interesting animals/algae that can help your tank mature.
Looks natural from the beginning
b) Disadvantages of using live rock:
May contain bad hitchhikers that can negatively impact your tank.
Expensive compared to dry rock

If costs are not a concern and you want to risk the bad hitchikers to make your tank look mature more quickly I would suggest you to buy rock that was taken from the ocean. Otherwise if you have the time and motivation, I would put in some aquacultured or dry rock in the tank and enjoy it maturing.
Concerning the amount of rock, you should just build an aquascape that you like as there are enough ways to create extra area for bacteria to grow.