Chiller disrupting water cycle?

[ania532]

Hi everyone! I recently set up a chiller for our aquarium, since it's getting warmer and warmer here in NYC. It's working great, but I just did my weekly water test, and... it seems the cycle has been interrupted!!! There is ammonia in the water again!! I am really devastated because it took ~forever~ to get the water to cycle back when we first set up the tank. Is it normal that a chiller would interrupt the water cycle like this? If anyone has any experience with this problem, I would love to hear their feedback/advice! Thank you so much!

 

[Murk]

Hiya!
I think it's unlikely an aquarium-safe chiller would have interrupted your cycle. In theory, I guess it could be possible for a sudden temperature drop to mess with your cycle, but such a sudden temperature drop would not be safe for any aquarium creature either, so I assume the chiller would not be that extreme.

Small ammonia fluctuations can still happen in a cycled tank. The tank being cycled just means you have a solid population of nitrifying bacteria, that eat the usual production of ammonia. If the tank suddenly produces more ammonia than normal (because left-over food has gone unnoticed, because a plant has dropped some leaves, heck, even because your axolotl took an unusually large poop), you will still measure a small ammonia spike.

The increasing temperature (from before you installed the chiller) could have played a role as well, since higher temperatures means ammonia forms more quickly.

In general, your bacteria population will adapt to small ammonia spikes rather quickly (probably followed by an even smaller nitrite spike). How much ammonia did you measure?
If it's more than a little spike (but a big spike instead!) you might want to search for the cause and do a water change.

 

[ania532]

Hi hi! Oh thank you so much for your message. The test tube looked to be in between 0.25ppm and 0.5ppm (sometimes it's hard to match exactly against the color guide the API test kit provides!). Which seems like a smaller-level spike, I guess? I checked the tank and found some dirt particles that must have come from an earthworm, and there was also a little dead fly floating on the surface. I cleaned those up and did a water change... but you know, now that you mention it, he DID have a big poop recently! So maybe that could have been the culprit. Anyway, it's good to know that these spikes can happen even in a cycled tank, I was terrified we'd have to go through the cycling all over again! Will test the water again today and see how it is doing now.

 

[Murk]

Hmm. To be honest, 0.25ppm (and especially 0.5) is more than I would have expected, and definitely more than you'd get from a little bit of dirt or a dead fly.
I still think it doesn't necessarily mean something's wrong with your cycle, but then there must be another source of ammonia somewhere. I'll be interested to hear how it develops the coming days!

 

[ania532]

Oh shoot! I will do another inspection of the tank to make sure there's not anything I missed...and test the water again tout de suite.

 

[ania532]

Hmmm, today's water test shows something in between 0 and .25 ppm of ammonia... so at least it's gone down a lot, but there's still a little bit in the tank. I couldn't find any other source of mess in there... I guess I'll just do another water change and hope for the best!