Selecting live rock can be confusing if you don’t know much about the bits and pieces of information surrounding this important topic in saltwater aquarium keeping.

Saltwater Aquarium Live RockAs we know aquarium live rock is an extremely effective filtration media to use within the saltwater aquarium. Not only does it provide filtration it also makes the aquarium look more natural.

With so many different types of live rock available, which one should you choose and how much do you need?

This article hopes to give you insights and to help you to be on your way to selecting live rock for your saltwater aquarium.

When setting up your aquarium you should have an idea as to what you want to keep and also what you hope it to look like.

During the planning stage you should have looked into the following as well as numerous other aspects:

  • Location
  • Aquarium size
  • Overflows (if required)
  • Stand design
  • Plumbing (if required)
  • Filtration basics
  • What you hope to keep
  • etc…

Of course there are various different types of primary filtration you can choose for your aquarium. It is up to you the aquarist to decide, however for the purpose of this post we will presume that aquarium live rock is the filtration of choice.

How much live rock??

The first thing that you need to work out is how much live rock you are actually going to need in relation to the amount of water in your aquarium.

Saltwater Aquarium Live RockThis is of course a hard aspect to work out as it does depend upon what you are keeping and how much “stock” you will have in your aquarium – it is presumed that you will not be overstocking…..

…..of course you won’t – good.

There is another variant when it comes to selecting live rock and calculating the amount that you’ll need in your aquarium. It is the type of live rock you will actually use. There are various types you can use.

For this example I will base the calculation upon fully cured Fiji live rock as this is the most common one used.

The basic calculation to follow is that you will require 1 1/4 to 1 3/4 pounds per gallon of water in the entire aquarium system. When you are working out the gallonage of water remember to include the sump if you have opted to use one.

Now you should be in a position where you know how much water your aquarium hold before displacement and how much live rock you roughly need. If you are not completely sure about how much live rock you will need then purchase a bit more just to be safe.

Buying and Selecting Live Rock

Now comes the fun part – purchasing it.

Again in this example I will base this post upon fully cured aquarium live rock.

There are effectively 2 ways you can purchase live rock – one is via mail order or the internet and the second is in person.

I personally prefer the latter option as you get to physically choose the pieces yourself.

With this first option someone, somewhere will choose the pieces for you and you effectively get what is delivered. This does have benefits however which are normally down to cost. If you shop around in magazines and on the internet you can get a great deal.

The second option of selecting live rock yourself is more fun though but what do you look for?

When you visit the shop have a good look around the shop first to see what sort of condition their aquariums, fish and corals are in. This will give you a good estimate as to how the shop is run and how things are maintained. If you have already built a relationship with a local fish shop then this should not be a problem for you.

Saltwater Aquarium Live Rock

Have a good look at the live rock holding tanks and see what the pieces look like. If possible ask about their curing process and ask if you can see their curing vats.

This is good as again you can see how they cure them and how much care is put into preserving the life on the rock. This is not always possible as some shops purchase live rock in fully cured.

When it comes to selecting live rock, you should have a rough idea as to what you hope your live rock structure(s) to look like. Bear this in mind when choosing the pieces. Have a good look at the pieces, ask for pieces to be removed for inspection if you can.

What you need to look for is that there is nothing decaying on the rock and especially that there are no pests present. This may take some looking for and you may have to be patient but it is worthwhile. Imagine how devastated you would be if you got your purchases home and a huge bristleworm for example poked out of the rock!

Look for good coralline growth on the rocks. This shows that the rock is of good quality and has come a good quality stock. You will probably not get a great deal of things appear from the rock after it is in your aquarium.

You might get some but that is not why we are selecting live rock, we purchase it for its magnificent filtration capabilities not for what might grow. If anything does grow then this is a bonus.

Try and pick pieces which will help you build the structure you desire. You will never get pieces which are the exact fit, however, you can do the best you can. It will make aquascaping a lot easier later on – trust me.

Once you have made your selections the shop employee should remove them and pack them into a suitable container.

Normally they are wrapped in paper or something similar so that the rock can remain damp in transit.

They are left damp so reduce any further die off while they are on the move between the shop and your aquarium.

There will be some die off experienced, however, if packed correctly this should be minimal.

You are now in a position to be able to take your aquarium live rock home and begin the fun part….

… aquascaping!

Nature's Ocean 12-Inch Coral Base Rocks for Aquarium, 40-Pound
Nature's Ocean 12-Inch Coral Base Rocks for Aquarium, 40-Pound
Aquarium Decorations used for Conserving Natural Reefs; Perfect for Coral Farming, Culturing Live Rocks & Growing Live Coral
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Caribsea Life Rock, 40-Pound
Caribsea Life Rock, 40-Pound
Made in USA; Package Weight : 39.999 Pounds; Package Dimensions : 10.0 L x 14.0 H x 2.0 W (inches)
Amazon Prime
Carib Sea ACS00372 3 case South Sea Base Rock Bag for Aquarium, 10-Pound
Carib Sea ACS00372 3 case South Sea Base Rock Bag for Aquarium, 10-Pound
No curing needed, South Seas is ready to use right away; It makes the best live rock to, takes coralline algae beautifully
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Related Articles:

 Live Rock and its Purpose

 Most Common Saltwater Aquarium Filtration System

 Filter Media

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