Ammonia help?

[joeyjoeq]

These week I've been noticing the ammonia level goes up to .50ppm then back down, up to .25ppm, then back down. At the time it is up at .50ppm. Tank is a 12g with 13-14lbs of LR. There is no fish in it, just my CUC. Have no been feeding, and really puzzled why this is happening?

 

[S.Reef]

Im assuming the rock came in uncured.semi cured? if this is the case i would just wait it out not even worry what level the ammonia is. When the level spikes like that its nothin to worry about probably some stuff on the rock that is dying or died...in few weeks you probably should not have any readings of ammonia.

 

[TRe]

id imagine its the lr dieoff let it fully cure (about 1-3 weeks)

 

[joeyjoeq]

Level came down last night. Thankfully*crazysmil it was the sponge I had stuck in the back of the tank. Completly forgot to rinse it when doing my water change.