Cycle question

[Jobu]

Hi there. I recently purchased an 80 gallon tank to upgrade from my current 30 gallon tank. The 30 gallon is pretty well-established (up and running for well over a year now), with 40 lbs of live rock and 30 lbs. of aragonite-based sand. The bio-load is pretty small, just one oscellaris clown, a cleaner shrimp, and a handful of little hermit crabs and snails for cleanup. My plan after getting everything setup in the 80 gallon is to move just my existing livestock over to the larger tank (no new additions right away). My question is, would I still need to cycle my 80 gallon tank if I migrate all of the live rock and substrate from the currently established 30 gallon tank? Or would bringing over the bacteria from the 30 gallon's live rock and substrate be enough to manage my small bioload? I know I will need more live rock for the big tank, and plan on getting it once everything is set up, but I was wondering if I could skip the cycle in the larger tank by bringing everything over from my existing one. Thanks!

 

[tcarola154]

in my experience, yes this would be fine. I switched a clown and a damsel out of a 10 gallon into a 45 without a problem... ( used the 12 lbs lr i had and another 15 precured from the lfs)

 

[runway1]

I'll be doing the same from a 55 to a 120. I here from this board that the concern is churning up your sand during the process. This will release.....ugly stuff and induce another mini-cycle.

Comments?

 

[Jobu]

Hm, I suppose a way around that would be to lay down new substrate in the big tank, and then only bring over a few cupfuls of your old sand to seed it. That way you won't be breaking down the entire bed, and the new substrate will eventually seed via the cupfuls from the old tank plus the bacteria on the live rock that you drug over.

This is just a theory tho, since I've never actually done it myself. Anyone see any problems/issues with this?

 

[drm]

I just switched over my 30 gal to 100 gal. I did lay down new substrate, used a small amount of old substrate to seed it. Transferred all of my old live rock, corals, etc. Then I used my old tank with remaining sand to cycle my new live rock before putting it into the new tank. All went very well. I did this within the past 6 weeks and have tons of pods, lots of evidence of good life. I am just now adding the new live rock to the tank.
In a different situation previously, I did do a transfer where I stirred up all of the sand, which created an ammonia bump, but only to 0.5, no nitrites or nitrates due to well-established tank.
Just my experience.

 

[sdellin]

I moved a 15G into a 55G by relocating all of the sand, live rock, etc. I did not get a new cycle right away, but that happened after I added some new rock that was not live rock. The mini-cycle started because I added too much dead rock at once (according to my lfs). However, it wasn't bad, just some diatom algae for awhile that cleared up on it's own. Now it's fine.

It's best, imo, to seed your new tank with the old sand, or at least with some of the old sand, rather than start a whole new tank cycle. As I stated, I didn't have a problem with moving over all of the sand.

 

[JG]

I went from a 30 gal to a 90 gal - moved old rock over but had new substrate. Used old substrate and water to cure new live rock.

I had a mini - cycle but nothing dreadful.

 

[robertfah]

I'll be doing the same from a 55 to a 120. I here from this board that the concern is churning up your sand during the process. This will release.....ugly stuff and induce another mini-cycle.

Comments?

IMO, it's prob. best to let the tank cycle. The tank upgrade is a slight increase in gallon size, but as other people have posted, you main concern is stirring up the old sandbed and throwing things out of wack. If your 30g has been setup for sometime now, just setup your 80g and place some of the LR in there along with more LS and aragonite and let it cycle while the fish are still in their old home. This way you can avoid stressing out the fish incase the levels spike.