Adding LR to tank

[Onebb]

Can you add more live rock to a tank that already has a few corals and fish in it? WIll it create any cycle or nitrate spikes? Thanks.

Onebb

[Crab Rangoon]

Are you adding new LR that is already cured, or uncured stuff? If planning to add uncured stuff, I would venture to say that 10% of your current total LR (if you have 50lb, adding approx 5-7lbs would be the max) to an existing tank is within safe tolerance of not disturbing the aquarium. Different people may have a different experience with it, and it really becomes almost irrelevant if your system is a large volume (think 200+ gal) or if you've already got over 150lb of rock.

If you're getting more uncured rock than your tank can currently handle, you're always better safe than sorry - just let it bubble all alone in a trash can or bucket until it's all ready to go.

For cured rock, and dry rock, I wouldn't worry about it unless the new addition were literally doubling your total load.

HTH

[Zarathustra2]

If you are adding uncured rock make sure to cure it in a separate container. There is a lot of life on a piece of live rock and it is all dead if it is "uncured." This will cause a significant nitrate/nitrite spike in your tank and at the least will cause a "mini-cycle." I even recommend "curing" live rock that is already cured and shipped or brought home from the fish store. Sometimes its not necessary but other times you catch a big patch of sponge that would have caused serious issues in your tank.

For curing just use a medium sized Rubbermaid container (I'll use a bucket for small amounts.) Add a heater and a powerhead in fresh saltwater. Change out a good amount of water every week. Usually just takes a month or so for uncured, maybe two weeks to cured. Just test the nitrates every couple of days to track the cycle.

[DaJMasta]

+1 to curing it in a bucket/rubbermaid. The method described works, but I much prefer the soft cycle, as it keeps more stuff alive and takes less time. Instead of changing water every week and waiting a month, do a 50% water change every day (I tend to do 2 on the first 2 days) and the cycle will be over in about 2 weeks. Yes there won't be quite as much nitrogen cycle bacteria at the end of the cycle, but there will be more hitchhikers in better condition and it will take a fraction of the time. It's not an option with large tanks, but with a bucket or a nano it works just fine. If you go the soft cycle route, I would also keep the bucket lit with something for at least a few hours - it increases the likelihood that photosynthetic hitchhikers will make it through.

If it's straight out of another established tank, it may not be too much to worry about, but the more time spent in transport the more likely you'll see die off. If you're buying from the LFS it almost always needs to be cured, regardless of what it's advertised as, but the cure times and cycle strengths can vary.

[Onebb]

Thanks for you all's advice.