The idea behind the cycling of base rock will depend on the type of rock - if its dry rock that has dead organics on/in it (dry Fiji etc) then the cycle is to prevent the dead organics from causing an ammonia spike when u put it in a display tank. If it is clean dry rock (like Reefer Rock) then the cycle is to get enough bacteria to colonize the surface of the rock so that when you add the rock to a tank it can deal with the bio load of that tank.
Equipment Required:
* Large Rubbermaid type garbage bin (large enough to hold the rock)
* Source of Organic Waste (uncooked raw shrimp if the rock is clean)
* Artificial Sea Water (saltwater)
* Submersible Heater
* Power Head or Airstone
Cycling Instructions:
1. Stack rock into the large bin
2. Add freshly mixed saltwater so the water level is above the rock by a few inches - Specific gravity of 1.021 to 1.025
3. Install the heater and set it to 28'C (82'F) - The beneficial bacterial multiply quicker at higher temp's thus cycling faster
4. Install the power head or airstone to provide good water circulation - The airstone needs to be large enough to provide good circulation
5. Add a piece of 'live' rock from an established aquarium and place in the large bin (not required but will provide a good seed source of bacteria and potentially quicken the cycle)
6. Keep bin in a dimly lit area - This will prevent nuisance algae blooms from occurring
7. Add a source of organic waste if the rock is clean - an uncooked raw shrimp is ideal (if cycling rock like dry Fiji then no organics are needed as it should be full of it)
8. Test the water for ammonia, nitrite and nitrate levels every few days - If the ammonia and nitrite levels have stabilized at 0 after an initial spike the rock has completed the cycle and is ready to be installed in your display tank
It can take from 20-45 days
You need to be careful about the water changes though - changing water too often or when not needed will cause the cycle to take longer then needed.
Hope this helps.