Cycle killed or is it still going ?

Richards Aquarium · Nov 4, 2024

Hi, my fellow fish keepers. I'm writing for a friend. He has a small 6 gallon FRESH WATER TANK. I told him I would reach out to the professionals. I actually gave him the tank in question. He made a terrible rookie error and forgot to dechlorinate and killed all the fish. He did a 3 gallon water change added fresh water and all the fish died this was about 3 weeks ago iam just finding out about this cause he did not Want to tell me. So my question is this. His Ammonia level is at 0.25 nitrite is at 0 and nitrate is at 40 ppm. I'm thinking that somehow the cycle is still going he just recently in the last 5 days has been adding a very small amount of food to tank ever other day. Any thoughts are appreciated in advance. And I apologize that this is fresh water post. I keep marine fish and he is just starting the hobby.
Thank you Richard.

JTP424 · Nov 4, 2024

Not sure how much we could help being marine, concepts are similar regarding cycling. Does he have any biomedia to convert the ammonia? Did he add any bacteria to kickstart it? Live Plants to assist with conversion? If he hasn't done anything his tank won't ever cycle. What is he using to test ammonia? API? Use something else.
Also he should track his testing. That will show him the rise and fall, which will help determine if cycled.

saltcats · Nov 4, 2024

Richards Aquarium said:
Hi, my fellow fish keepers. I'm writing for a friend. He has a small 6 gallon FRESH WATER TANK. I told him I would reach out to the professionals. I actually gave him the tank in question. He made a terrible rookie error and forgot to dechlorinate and killed all the fish. He did a 3 gallon water change added fresh water and all the fish died this was about 3 weeks ago iam just finding out about this cause he did not Want to tell me. So my question is this. His Ammonia level is at 0.25 nitrite is at 0 and nitrate is at 40 ppm. I'm thinking that somehow the cycle is still going he just recently in the last 5 days has been adding a very small amount of food to tank ever other day. Any thoughts are appreciated in advance. And I apologize that this is fresh water post. I keep marine fish and he is just starting the hobby.
Thank you Richard.

What's he using to test ammonia? Nitrates reading above 0 means the tank is definitely cycled (ammonia is being processed through), and from my understanding anyway it's not really a "thing" to stall or "uncycle" a tank; once it's done its done.

The reason I ask re the ammonia is that figure makes me suspicious in a specific way; the API test kit is notorious for reading 0.25 when it's actually 0 ;)

Sorry about the loss of his fish!