Cycling a 275 tank

[Shluffer]

I'm new to "large" tanks. My system: 275 gallon display, 120 gallon sump. Live rock is from my old system, but half of it was dried out, half sat in buckets of water for a year (old tank was taken down when we relocated). I have about 250 pounds of LR, including the rubble rock.

Tank has been running for a week, salt level has been stable for 48 hours. Ammonia is 0, but I"m assuming it just hasn't spiked yet. Their is plenty of die off on the rocks, but will set up the auto feeder today.

My preference is to avoid subjecting any live animals to ammonia, but I'm not sure the tank will noticeably cycle given the ratio of water to rock, and I'm not excited about feeding it to the point that I would be guaranteed a spike. Given the size of the tank, and that a significant amount of rock was in water for the year, is it safe to risk a cycle with a small fish? I would assume that any ammonia spike would be small, and I plan to go very slow adding livestock.

My other alternative (if I can find it) is to does pure ammonia. Is there a calculation of how much I would dose?

 

[pluikens]

I would suggest using Dr Tims Ammonium Chloride. Dose your tank to 2ppm by adding 4 drops per gallon. Don't worry, you don't have to count over 1,000 drops! For example, let's say you have 350 total gallons:

350 gallons * 4 drops/gallon = 1400 drops
1400 drops * .05ml/drop = 70 ml
70 ml = 2.37 ounces

I'd suggest getting a couple 4 oz bottle because I like to dose up to 2ppm and see it be eliminated in 24 hours to confirm the bacteria is built up sufficiently.

 

[Shluffer]

Sounds reasonable. Will also give it a few extra days to see if I get a spike.

 

[brandon429]

any rock that remained hydrated didn't lose its bacteria. Its ok to feed w ammonia, or feed nothing. in 30 days underwater all your surfaces w have a basic biofilm coating due to association submerged with the formerly live rock.

live rock does not have to be fed to keep its bacteria, it needs only to be hydrated. even the salt leves are allowed to vary a lot and it will still keep bac, hydration is the must. seasonal garage temperatures will not kill hydrated live rock (bac portion) even if its fallow for years. you could easily let a fish swim about this mix for a month and that would speed things up without adding a bunch of organics, if you've got the time. 30 days will do it, this is the mixed substrate cycle portion of our cycling thread in the new keepers forum.

 

[Shluffer]

Thanks. That helps. The live rock was hydrated, so I should be good. I'm going to give it at least two weeks, probably 30 days. If I don't see an ammonia spike, I'll assume I'm good. If I do, I'll wait for it to go back to zero. I'm at two weeks now, so patience is the plan.

 

[brandon429]

Another detail to help, straight from cycling threads

It's the movement of ammonia down from a given rating within 24 hours that counts, not the bottom end to zero. Old cycling articles have that wrong.... Not in theory, but in application as most people's ammonia testing varies at low levels such that .25 is zero. We had to account for that with new materials.

So if your kits detect even a halving of ammonia, that's complete verification.

There is no biological model for sustained low level ammonia in reefing given all animals and nutrient stores accounted for. No condition in reefing outside medication events will oxidize 90% of a given bioload, and leave a dangerous ten pct... That's test misread zone. true 1-2 ppm ammonia levels are far beyond what we'll be stocking in fish loads for most tanks, once a reef can cause movement down from 2.0 then by rule that surface area is enough to handle the correct bioloading from the stocked tank which is less than the cycled amounts. of course duration of submersion of the surfaces matters 100%, we're talking only submerged surfaces like you have and not a system where added bottle bac in suspension is oxidizing ammonia, that's opposite of our goal and measure.

Movement at all measurable in 24 hr means ready. No rush, but that's handy info. A month more allows more curing, that's helpful.