What's new

Cycle Question


Fish Fanatic
Dec 26, 2017
Reaction score
So there is a tank in a house that was sold as is, its a 29 Gallon, looks pretty much new, and the accessories look brand new so I'm assuming very recently set up.

However, has 3 pictus catfish, an Angel, 2 bristlenose plecos, 4 Ottos and 5 cories.

Just did a water test:

Temp: 79 Degrees
pH: 8.2
Ammonia: 0ppm
Nitrite: 2.0ppm
Nitrate: 5.0ppm

So I'm assuming maybe partially cycled?

What can I do to help this tank out? The fish I guess seem fine but I heard Nitrite kills from inside? The catfish seem to be going a bit crazy, but might just be the way they are, cories not really moving at all.
I have shut down my tank as I am currently moving, all the fish are up for free right now but no interest yet.

Do I just do 50 percent water changes every day?



Jan 26, 2008
Reaction score
Perth, WA
Reduce feeding to a couple of times per week.
Do a 75% water change and gravel clean the substrate 4-8 hours after feeding.
Do a 75% water change and gravel clean the substrate any day you have an ammonia or nitrite reading above 0.
Make sure any new water is free of chlorine/ chloramine before it goes in the tank.

In a couple of weeks the filters should have finished cycling and the nitrite will drop to 0 and you can start feeding more often and do a 75% water change and gravel clean once a week.

Pictus catfish are pretty active, especially when food is added to the tank.
The Cories are probably stressed from the nitrite. The water changes should help.


Dec 31, 2004
Reaction score
On Another Site
I have not posted here in a very long time. I wrote the three cycling articles this site uses. I would not follow advice to change water. Instead, I suggest you read this article, especially the part about nitrite here http://www.fishforums.net/threads/rescuing-a-fish-in-cycle-gone-wild-part-il.433778/
Since you show 0 ammonia, this is not the issue, nitrite is, so please go right to the section on "SOME FACTS ABOUT NITRITE" You likely have sufficient ammonia oxidizing bacteria built up, what you lack is nitrite oxidizers.

By doing water changes you will not eliminate nitrite from the fish, this can only happen by removing nitrite from the fish. The only way I am aware of to do this is using Methylene Blue which will stain things in a tank. Otherwise removing nitrite, once at work inside a fish, is done by time, it comes out naturally over 24-48 hours as long as there is not more nitrite entering the fish. A water change only lowers nitrite, it does not remove or block it.

By using chloride (i.e. salt) you prevent more nitrite from entering the fish and the natural processes will clear out what is already there. By leaving the nitrite alone (as long as it doesn't exceed about 15 ppm), the needed bacteria will multiply faster and solve the problem sooner.

It is important to understand that ammonia detoxifiers and water changes tend to slow a cycle. They should be avoided as long as the fish are not threatened or they are not high enough to stall a fishless cycle.

I doubt I will be posting agian in the near future, I have not visited here much in the past few years/ I popped in out of curiosity and though this info would help you. Good luck.