[papagimp]

I wouldn't add anything with nitrite showing up at all, that's an indication of the tank not being cycled or recent ammonia/bioload being added beyond what the tanks filtering capacity can handle. . Probably due to the added rock after the initial cycle. Uncured rock or live rock with excessive die off can/will cause more ammoina and nitrite spikes.

May also wanna get a second opinion on the test if it keeps showing up. Some test kits are highly inaccurate.