Kashim

I have a 55 gallon tank that's about 2 months old. In the first month I was testing my water a lot and the readings were always good, even before the tank was fully cycled. My ammonia and nitrite levels were always at 0 or at the lowest level my kit could detect. Then about a week ago my nitrite levels suddenly shot way up to 3.3mg/L (that's the highest the kit can detect) and I can't get them to go down. However, my ammonia levels stayed at almost 0 and only spike after vacuuming the gravel and then go back down after 24 hours.

As soon as I noticed the nitrite spike, I did a 25% water change and then another 25% the next day. My readings did not change. Then I realized my mistake. I was not vacuuming the gravel properly. I wasn't vacuuming the gravel all the way to the bottom of the tank, only the top layer. So the next day I started a full vacuum of the gravel. I did about 2/3rds of the gravel and 30% water got changed. Of course there was a lot of waste hidden at the bottom and it turned my water to . Both my ammonia and nitrite levels spiked. The next day day I did the remaining 1/3rd of the gravel and another 25% water got changed. This was probably another mistake, vacuuming too much of the gravel too fast. The next day my ammonia levels were fine, but my nitrite was still too high. This was two days ago.

Today I did another 25% water change without disturbing the gravel and my nitrite levels seem to have gone down a little, but they're still too high. It's still around 1.6-3.3mg/L and I don't know what else to do. I'm getting really tired of all these water changes day after day that seem to have no effect.

During this whole ordeal, one of my cories died. The rest of my fish seem to be fine for now. I have no live plants in my tank, only plastic ones and decorations. This is what I have right now:

8 neon tetras
7 cherry barbs
6 guppies
5 cories

Any suggestions would be appreciated.

Alessa

What water conditioner are you using? are you changing the filter at all?
In this situation there is little that can be done other than daily water changes with prime. Another thing you can do is get Tetra Safe Start, which is supposed to cycle the tank instantly.

jdhef

It sounds to me that you are half way thru the cycle. It appears that you have the bacteria that converts ammonia to nitrites, but not the bacteria that converts nitrites to nitrates. Like Alessa says, continue the daily water changes using Prime or get Safe Start. Also getting some filter media or gravel from an established tank and placing it in your tank would speed things up.

Also, try not to over feed you fish, since the left over food will turn to ammonia and then converted to nitrites.

Kashim

The nights are getting pretty cold here, so I adjusted my water heater from 26C to 28C, but the water temp never really goes above 26C by much. My tap water has a pH of around 7.8 and it's very hard. I used some pH down to lower it to around 7.2-7.4 over the course of a week. I changed one of my filters on the day this whole mess started. It was about 3 weeks old at that time. Then a week later I changed the other filter. I have the kind of power filter with two sets of bio filters and two sets of carbon filters.

I use Prime every time I add new water. I add a bit more than they recommend, because my tap water has a lot chlorine in it. I also use Stability (it's by the same company as Prime) which adds the beneficial bacteria. It's supposed to help cycle a tank in about a week. I've been adding it daily for over 3 weeks now, well before this whole problem started. I was originally using Cycle for the first month when I got my tank, but then I found out it was . Apparently it uses a type of bacteria that isn't self sustaining and you have to keep adding Cycle to your tank forever. That's why I switched to Stability and have been using it 3 times longer than they recommend on the bottle. Stability is the best thing I can get here, because they don't sell Tetra Safe Start in Canada. I guess I'll do a few more water changes and see what happens.

Shawnie

unfortunately, adding ph up n downs messes with the cycle...fish are ok with all kinds of different ph's as long as they are stable and not changing often..so I wouldnt worry about that much...at this point, you have gone back to a cycle because of the filter changes...those only need to be changed when they are total threads and falling apart...otherwise just a rinse in used tank water is fine...daily water changes with prime will help your fishies deal with the nitrites until the cycle completes again...goodluck

Kashim

I didn't change or remove the biological filters. I changed one of the carbon filters and then the other one a week later. The package says to change them every 2-4 weeks and the ones I removed were around 3 weeks old. I did pull up one of the bio filters just to take a look and there's a thick layer of "stuff" on it, which I assume is the bacteria I want.

Aro

This is true. Change the carbon filters every 2-4.

Are you are vacuuming right? When my sis vacuums her 46 gallon she pushes it all the way to the bottom holds it down for a little bit to get all the stuff out.

Lucy

I don't use carbon since it can expire. I cut a slit in my cartridge and empty the carbon out. Then I only rinse the (carbonless) catridge when it gets gunky and only replace it when it's falling apart.

Each time you throw the cartridge out, you throw out a good deal of the benefical bacteria that grows there.

capekate

Hi Kashim
IMO it sounds like you are continually going through mini cycles. You did mention in another post that you take out all the decorations and clean them as well as vacuuming the tank.
The stability is like the Cycle product in that you have to continue to use it for it to work.
Personally I would use Prime only for the water conditioner. If you are using a PH down you have to use it every time you do a water change. During the time in between using the PH Down, your level of PH will start to slowly raise, til you add the next dose with water change. I believe this fluctuation is not good for your fish and as others mentioned, this and not a high Ph is what is bad for your fish's health.
I have had mini cycles from going gung HO with the cleaning til I learned, that by doing only half the cleaning of decorations once a week was best, and saving the other half of decorations for the following water change.