Is my tank cycled?

[Cincotta82]

Hey All-

My tank is 3 weeks old (28g nanocube led). I added LS (30lbs), bio-spira, and 20 lbs of Pukani Dry rock. 2 days later I added 9 lbs LR to seed DR. I began testing basic parameters every other day. This is what I've found:

NH3- .25ppm, lowered to 0.00 in 5 days, now indiscernible b/n .25-0.00 since.

NO2 - 0.00ppm, saw spike to 1.00 in 7 days, dropped to nearly 0.00 since

NO3 - 0ppm, gradually rose to 10ppm in 5 days, 7 days 20ppm, since hovering b/n 20-40ppm

The reason for my confusion is the Bio-Spira. Not sure what trend I should be seeing after using this product.

I saw a diatom bloom after around 4 days. It's still there in some sense, but has been fading ever since.

Can someone please dissect this madness??????

THANKS GUYS!

[bnumair]

i have successfully used bio-spira in brand new tank with new water nee dry rock with no cycle. i also seeded with a little live rock.
anyways to answer ur question if u want to be 100% sure ghost feed ur tank today and check for ammonia tomorow. if still 0 ur tank has cycled.

[Cincotta82]

Wow, thanks bnumair. I never thought of testing by adding ammonia in the form of food.
Appreciate the advice.

[Sethjamto]

And then if no ammonia tomorrow, do a water change to reduce the nitrates and get your CUC going. Fish can be right around the corner from that. Have FUN!

[coralsnaked]

I would be suspicious of dry rock cycling completely in 3 weeks Keep testing and the ghost feeding is a good suggestion.

Happy reefing

[ATLJonathan]

Once you see the presence of nitrates your tank is cycled. however, that doesn't mean that it won't cycle again, it all depends on the amount of beneficial bacteria that is present. Always keep some of Dr. Tim's One and Only or BIO-SPhere available.

[Cincotta82]

Thanks all for the responses. Again, my issue was that I never saw a huge ammonia spike (I thought this was due to the introduction to biospira). I ran parameters again last night (this is entering my 3rd week):

NH3 ~ 0.00 ( a little darker than the 0.00 color on the test strip, but no where near the next level 0.25)

NO2 0.00 (it's been this except 1 spike over the course of 2 days, about 1.5 weeks ago, to 1.00)

NO3 20ppm down from 30-40ppm (which remained constant for 1 week)

FYI - My diatom bloom has lessened on the rock over the last 6 days.