JennDFK

What is the difference between a crashed cycle and a mini cycle? How do you know which one is happening in your tank?

Lucy

Uh oh Jen, I hope neither has happened to your tank.
A mini cycle is when for some reason you're showing a bit of ammonia or nitrite in a tank that was cycled.
A crash is when you completely (or almost) lose the cycle.

JennDFK

Well I'm showing both ammonia (.5 PPM at least) and nitrite(.25ppm) in my 55 gallon. I have been doing 15-20% water changes daily for 5 days I think... I just was wondering what I was in for... was thinking about cutting a chunk off my filter media in my 30 gallon to introduce some bacteria... but I don't want to throw that one into a cycle too.

Lucy

The 55 was cycled, wasn't it? Had anything changed? Stock added etc?
IMO, it looks like a mini cycle. Just continue with the water changes and prime.
You could try moving some gravel or a decoration over. If the 30 is well established, it shouldn't have any effect.
In the mean time, put some extra filter media in both your tanks. You'll be ready if it happens again.
Good luck

JennDFK

It was newly cycled... I introduced fish...and they brought a nasty little illness. I think the combo of removing filter media to treat and the meds are causing the cycle troubles....and the fish still have some yucky fuzz growing on their mouth. No big deal really... just sick of doing daily water changes... and I want to help the fish.

I'm showing no ammonia this AM after a 30% (about 15 gallons) water change with extra prime last night... but the nitrates are still there. Looks like I'm doing another change tonight. I just want to get this under control before my vacation in 2 weeks.

Jenn

Shawnie

answer to the op is a mini cycle shows up with ammonia or nitrites with an already cycled tank (nitrates in there) and a crash is ammonia or nitrites without any nitrates left I think you are in a mini and hopefully it gets better soon!!! the changes are going to help alot ....