Added 4lb Cured Rock, Nitrates Spiked

[Osse]

OK so I've got a 14gallon biocube that's been running for about 8 weeks now. It originally had 11.5 lbs of live rock, 3.5lbs live rubble, and 5lb live sand in it. I added 2 damsels about a week and half ago and a tomato clown this past friday. I added an extra 4lb rock on Saturday, and the nitrates we're fine until yesterday-hovering around 5. However, I had the bright idea to stir up the substrate a little to move it through the filter. Nitrates climbed to 10, and later in evening jumped to 20. The fish we're getting a little skitzy so I did a 2.5gal water change. Nitrates are still hovering around 20-25. I know this is normal for new rock added to a tank, but will it stay high or will it drop quicker than normal b/c I already have plenty of cycled rock/rubble/sand in it? I have an extra empty tank lying around, so should I just move the fish to it until the nitrates drop or will they be fine in water hovering around 20ppm? Thanks for the help!

 

[drobbyb]

OK so I've got a 14gallon biocube that's been running for about 8 weeks now. It originally had 11.5 lbs of live rock, 3.5lbs live rubble, and 5lb live sand in it. I added 2 damsels about a week and half ago and a tomato clown this past friday. I added an extra 4lb rock on Saturday, and the nitrates we're fine until yesterday-hovering around 5. However, I had the bright idea to stir up the substrate a little to move it through the filter. Nitrates climbed to 10, and later in evening jumped to 20. The fish we're getting a little skitzy so I did a 2.5gal water change. Nitrates are still hovering around 20-25. I know this is normal for new rock added to a tank, but will it stay high or will it drop quicker than normal b/c I already have plenty of cycled rock/rubble/sand in it? I have an extra empty tank lying around, so should I just move the fish to it until the nitrates drop or will they be fine in water hovering around 20ppm? Thanks for the help!

I'm not a saltwater guy, but it sounds like it could be normal. Here's why: If the live rock wasn't cured properly then it brings in a new ammonia source. Your already established bio filter simply converted it to nitrite and ultimately to nitrate. The nitrate spike will continue as long as it takes the live rock to fully cure.