Cycle Stall?

[akkitten]

I did a fishless cycle on a 20g tall, waited patiently until my readings were consistently at amm 0, NO2 0, NO3 5 for over one week. Since I cycled at ammonia around 4 I knew I could add more than a few fish at a time. I added 6 zebra danios and sadly two died the first night and another the next day. Three days later (first opportunity) I went back to the lfs and got 4 more danio and a dwarf gourami. Water paramaters were fine before I added them. Now suddenly 3 days later I have a BAD NO2 spike, my paramaters are currently amm 0, NO2 ~2, NO3 10.

Is there anything I can do to bring it down fast besides pwc and Prime? It is a planted tank if that makes any difference.

 

[ejaramillo01]

This is strange. IMO the best thing to do you mentioned already: partial water changes.

Doing PWC increase the possibility for the cycle to continue its course.

 

[akkitten]

I thought it was strange too....sigh...so keep doing 50% a day and adding a little prime just so I don't hurt the fish? Is there anyway it could be a false reading on the NO2?

 

[mfdrookie516]

Have you tested it multiple times with the same reading? If so, I highly doubt you're getting a false positive. Hard to guess what caused it. Could have been the extremely low bioload of 3 danios causing the nitrobacter to 'starve' and die off. Could also be a number of other things. Looks like water changes are going to be your best bet right now. You may see them drop pretty quick, or it may take a few days. Just keep up on them until it does.

 

[Jason7894561230]

Or try getting some media from another tank that is established and put that in your filter. It will help with the cycle because it already has good bacteria on it

 

[marchmaxima]

Agree water changes are your best bet. It is kinda odd though.

Also just on the fish, how did you acclimate them? Did you by chance test that water that they came in? Its always possible that the water parameters of the fish shop's water was vastly different to yours and if that's the case, then a longer acclimation time is advised.

But that wouldn't be related to the NO2 spike. I hope you sort it soon.

 

[akkitten]

Fish were a acclimated by soaking bag and then adding tank water over about a 40 min time frame, they were netted and placed in the tank. No lfs water was added to my tank. I added some media this morning to the filter, thanks for the suggestion, will do another 50% pwc tonite and see how that goes. None of the fish seem to be in distress. ::shrug:: I am so confused.