What are the advantages of live rock?
• Live rock is the foundation of most successful reef tanks, just as it is the foundation of real reefs.
• Live rock is a good source of food for grazing and fussy fish. There are some species of fish such as the mandarin goby, which only really eat what’s on the live rock e.g. amphipods.
• If a fish is new, the live rock is what generally supports the fish until it settles in and starts to eat introduced food.
• If a fish is sick, live rock is often the first food it will accept, to help it get back to good health.
• Live rock can help to oxygenate the water.
• Live rock acts as a filter in the aquarium. The surface of some live rock is covered with photosynthetic life like algae, which helps oxygenate while it consumes the waste in the aquarium.
• Aerobic-bacteria is harboured by the rock, which aids in the breakdown of high level waste.
• Anoxic and anaerobic-bacteria forms in the rock where it can’t be disturbed, this also lowers low-level waste by converting it to gas.
• The insides of a piece of live rock could be described as like honey comb, presenting a mass surface area for zones of bacteria.
• Many other organisms on and in the rock play a role in adding to the filtration of the ecosystem.
• There are a lot of beneficial things in and on the rocks that are invisible, so just because some rocks look bald it doesn’t mean they aren`t good.
• Rocks with less growth can be better for new tanks because most new tanks can’t support a densely grown rock anyway.
• Saltwater aquariums tend to lack plant growth which grows on the live rock (plants oxygenate the water, consume waste, look great and provide food), enhancing the importance of live rock.
• Live rock is the backbone and lungs of the reef tank.

What are the disadvantages of live rock?
• It can be expensive.
• Pests can be introduced.

When do I put in live rock?
• As soon as the water is ready (correct pH, temperature, low waste levels and correct salt level).
• Live rock should be the first living thing you add to the aquarium. The first lot of rock is your only opportunity to add a large amount of life to the tank at once. This is possible because there is little at risk when there is previously nothing in the tank.

How much live rock should I use?
• I try to recommend adding the quantity that creates the best visual effect.
• If live rock is one of your primary filters try to make about 30% of the tanks volume replaced by live rock. Some people use the rule of about 1kg per gallon (3.8lt)

How should I place live rock?
• Ensure that the structure is as porous as possible.
• Try to receive maximum elevation with the rocks you have, don’ t pack them tightly together or debris will gather.
• Live rock has a bottom and a top. Try to keep all the greener parts on the rock up, exposed to the light and water movement. Any rock with lush growth shouldn’t be under another rock or it will go off.
• I don’t recommend using lush green live rock to create the elevation as most of the photosynthetic life on the rock underneath will die.
• The lush green live rock should be exposed to the light so it can carry out the tanks much-needed photosynthetic processes.
• The more growth on the rock the higher in the aquarium you should try to place it.
• The presence of sponge corals is a good indication that that side is the bottom.
• Generally the side with the least growth is the bottom.
• Try to minimise the contact between the rock and the substrate (shelves will aid this or simply place the rocks on their ends and don’ t allow pieces with large flat faces to lay on the substrate) because this will only encourage the build up of debris.
• It is best to allow enough room along the back wall to enable you to get a siphon hose down to the debris at the bottom. Shelves are ideal to allow you to do this.
• Roll living rock around in the tank before you place it to stop air bubbles being trapped under the rock.

Why is live rock used to start the bacteria cycle?
• Live rock is hardier and less expensive than fish and creates a natural source of food and protection for the fish when they are introduced.
• Live rock is used to cycle an aquarium because of the waste produced during the natural regeneration of the life on the rock.
• Bacteria form on the rock and feed on waste produced by the rock.
• If you want the rock to cycle quicker strip off any bulky algaes or sponges before you put it in the tank.

How long does live rocks take to cycle?
• Normally about 2 weeks with a protein skimmer.
• 4-6 weeks without.
• Ensure you follow your the water parameters set out in your logbook.

What is natural regeneration of live rock?
• Natural regeneration occurs when you remove a piece of live rock from one environment or position and place it in another.
• The rock is covered in millions of microscopic bacteria, crustaceans, and photosynthetic life etc that require particular conditions. When you remove a live rock from a particular environment and place it in another with possibly different amounts of light, water movement and temperature, things on the rock that can’t adapt to the new environment will die, while other things that prefer the new environment will thrive.
• That is why a rock in each different position can look different.

Should live rock be quarantined before it is added to an established tank?
• If you have a quarantine tank it would be most advisable to place the rock into the quarantine tank for a week or two before adding it to an established reef tank.
• This would also enable you isolate pests such as mantis shrimp.
• If the quarantine tank was previously run with copper ensure that at least one complete water change has been done. Adding carbon and/or a metal sponge to the filter can also help for this period.

What living things come in on live rock?
Some of the good things are
• Protozoa (unicellular animals) such as bacteria.
• Sponge coral.
• Crustaceans.
• Amphipods.
• Copepods.
• Molluscs (e.g. snails, clams).
• Echinoderms (starfish, urchins and sea cucumbers).
• Sea squirts
• Algae

Some things to be careful of
• Sea spiders
• Flatworms
• Bristle worms
• Shrimp (Mantis shrimp)
• Crabs
• Colonial Anemones
• Baby Octopus

How do you handle live rock?
• You must be wary when handling live rock because it may contain creatures like mantis shrimp that can whack you, bristle worms that can bite you and corals that can sting you.
• Hold the rock on your finger tips not in your palms (this will minimize your contact with the rock).
• It is safer to wear gloves.

Should the lights be on during the seeding period?
• It is best to have little or no light during this time because the high nutrient levels will spark unnecessary algae outbreaks.
• If the rock is covered with lush green growth you may wish to leave the lights on and allow an extended cycle period.

What is the white stringy stuff coming off my live rock?
• This is just an excretion, often dead sponges, corals, clams, algae and worms that can’t adapt to the change and is all a part of natural regeneration.
• Do not worry just siphon it off.

Does live rock smell?
• Yes, don’t stress, sometimes it smells very bad especially out of water. Once the tank settles down it should have very little or no odor under the water. The more it smell the longer it is likely to take to cycle.
• A protein skimmer, water changes and carbon help to stop bad smells.
• Often sponges, corals, clams, algae, and worms damaged during transportation die and emit an odour.

Why did my tank water go yellow after I added the live rock?
• This is just the result of the organic compounds that are released from fresh rock.
• Activated carbon, protein skimming and water changes will soon fix this.

Can you make live rock?
• In a way yes you can because if you have a tank with some live rock and some dead rock over time the live rock will spread to the dead rock causing it to be alive too.
• Coral skeletons are the best base to use in order to make live rock because it is essentially what real live rock comprises of.

What does live rock feed on?
Live rock feeds on organic waste, trace elements and the light.

Can I add fresh live rock to a mature aquarium?
• Yes but be very careful, only add a very small amount at a time because the new rock will have to go through a new regeneration cycle that may cause an imbalance in the aquarium`s chemistry.
• Be careful with new rock so that it doesn’t create a new unwanted algae bloom or release a new pest into an otherwise great tank.
• Some people mature new rocks in their mini reef filter. This will minimize the introduction of algae because of limited light and enable you to identify pests. This is especially possible because the new bits are normally small.
• Algae introduced on a new rock may cause a bloom in the tank.
• This algae may change forms several times before it becomes calcareous and can be controlled.

In a new tank how long after adding live rock can you add fish?
• Once the parameters are again favorable (see log books) you may add a small amount of fish e.g. 2 or 3 hardy, cheap, non-destructive fish like clowns, cardinals or chromis.
• The longer the better, though 2 weeks is about the norm.
• After the first lot of cheap fish have settled in, fish algae eaters such as tangs are good as the next choice to help control algae.

How is live rock the best biological filter?
• This is because any low-level waste that is created by the breakdown of high level waste (by aerobic bacteria) is passed on to the anoxic and anaerobic bacteria within the rock. (The anoxic and anaerobic bacterium then denitrifies the low-level waste).
• This is the same form of filtration used in the very ecosystem that we are trying to recreate (the reef).
• The rock in the tank is the first thing that comes in contact with the waste that is produced in the tank.

Where is live rock from?
• Most live rock is gathered in and around a coral reef.
• Rock farms are being established to minimize natural impact, these farms will become increasingly common. Even to the point where they may be able to supply all of our live rock demands.

What is the squirt of coloured liquid that was expelled from the live rock?
• Its is quite possible the coloured liquid that is squirted out of the live rock was caused be a previously undetected baby octopus that managed to hitch a ride into the tank in one of the cracks of the live rock.
• Anemones will sometimes also expel coloured liquid.

Why have starfish (or other echinoderms) crawled out of the live rock and died a few days after the rock has been introduced?
• This is because they sometimes die (even after a few days) after they have been out of the water for any period of time.
• This may also be because during the aquarium`s early cycles the organic waste level may have reached a level that is toxic to them.
• This may also be because there may even be another creature that has come in on the rock that is killing them.

by Paul Talbot