Nitrite Issue

[puffers4puffers]

Why are you testing?
if the new water is ”proper water chemistry“
and you're doing significant water changes with regularity
you should be OK
don't chase numbers
the solution to pollution is dilution
feed the fish, flush the toilet

 

[Cal Amari]

Do you use dechlorinator? Glad it's gone, but can't o,agine what would cause a spike in nitrites but not in ammonia or nitrates unless there was some change in the bb colony, besides a testing error which happens to all of us sometimes

 

[Teddy99]

Do you use dechlorinator? Glad it's gone, but can't o,agine what would cause a spike in nitrites but not in ammonia or nitrates unless there was some change in the bb colony, besides a testing error which happens to all of us sometimes

I do use dechlorinator, yes.

 

[esoxlucius]

I've never been a great fan of adding "things" to the tank which claim to remove by products of the nitrogen cycle, in your case, Zeo Carb.

The reason being is that a healthy filter should more than adequately be suitable to perform those duties.

And don't forget, many of those products, Zeo Carb included, have an operational shelf life as it were. You have to periodically change them out for new or they can leech the very nasties they've removed back into your tank!!

Is there a possibility that your Zeo Carb is past it's best, and is leeching stuff back into your tank?

Personally I'd permanently remove the Zeo Carb and swap it for bog standard bio media.