Nitrite Issues

[Ephuntz]

Hey There,

So I set my tank up 3 months ago (freshwater), and cycled it for about a month following what the local fish store guy told me to do (it's an exclusive fish store not some place like petsmart, etc...)... I put stability, etc... in and let it run. I tested my water and as advised slowly started introducing fish while regularly checking my chemistry. everything was going fine for about 2 months then kerpow! nitrites way above detection limits of the API water tests. I'm at a loss for what to do with this, I've been doing water changes, adding prime, etc... and the nitrites aren't budging... my nitrates have also been between 5-10ppm for the last two weeks as well. I don't think my tests are faulty as I've now lost 6 fish in the last week (about 1/2 my population).

Any advice on what I can do? I've done large scale water changes 50+% and I test immediately afterwards (like within 10 min of completing the change) and my nitrites are still above the max.

 

[Aiken Drum]

Any nitrite is a sign you arent cycled. There can be a few possible reasons for this.

1. You did something to crash your cycle. Did you do any tank or filter maintenance in the run up to your problems? Overcleaning can kill off all the microbes responsible for your cycle. Replacing filter media or filter cartidges will result in you simply throwing those microbes in the trash.
2. Your system just simply cant cope with the amount of waste going in the tank. Either fish waste or fish food. What size is your tank? What is your filtration? How many fish do you have and what kind? Are you sure you arent overfeeding?
3. There is some other ammonia source that wasnt there before. Maybe your water company did some utility maintenance and overdosed on chloramine to clean out the pipework. They often do this before the summer months. Chloramine will be an ammonia source, so changing water will be adding to your problem. Test your tap water to see if it has any ammonia in there. Maybe something died in there and you havent noticed it. Its now decomposing and causing a water parameter issue.

What to do? Assuming your tap water is free of ammonia water changes. A 50% water change will reduce the nitrite by 50%. 2 x 50% back to back water changes will reduce nitrite by 75%. If its off the charts high, thats above 5ppm. At that sort of level you would need 4 or more 50% water changes to get to a safe level. Cut back on feeding to reduce waste going in. Only feed every 2 days. Keep up with whatever big water changes are needed to keep the water safe until you are sure your cycle is established.

 

[Aiken Drum]

Another question.

What filter media is in your filter? Is there anything that might be ammonia reducing chemical media like zeolite? What does it say on the packaging it all came in?

Ammonia reducing chemicals only last for so long before it stops working and then you start seeing water quality issues. These chemicals remove the food source the microbes responsible for your cycle feed on. They prevent your cycle from establishing but give the temporary appearance of being cycled.

Remember that nitrite comes from ammonia, so you should be looking to ammonia as the cause of your issues. Also in a cycled tank you should see nitrate. The levels of nitrate you are seeing isnt a problem. In fact if this is the first you are seeing of nitrate its a sign you where never cycled.

 

[Ephuntz]

Hey Thanks! I'll just reference you points....

1. I don't think so? I did vacuum once but I didn't do anything extensive. I never messed with my filter either.

2. My tank is 40 Gal (probably only 37-38 gal of water in it), I have an AquaClear 75 gal filter, I have 7/8 Zebra danios, had 5 Platys, 4 Corys, and 2 Angelfish (which may be large for the tank but I was told they'd be ok)... this was probably going to be the max I was going to put in... maybe add some swordtails later with a smaller pleco and shrimp. I am feeding every 1.5 days or so.

3. I tested my tap water and it all seemed ok... I also add conditioner to it to deal with any chlorine, etc...

I'll start doing regular large water changes... perhaps I'll do 4 50% ones tonight to see what my tests look like.

 

[Ephuntz]

As a follow up to your 2nd question...

The filter is a 3 step filter, 1st a sponge/filter floss, 2. carbon filter, 3. "biomax" looks like zeolites, it claims this part reduces ammonia and nitrate.

my ammonia tests show 0-0.25ppm ammonia...

My tests are 7.4 ph, 0-0.25ppm ammonia, 5+ ppm nitrite, 5-10ppm nitrate... my tanks temp is 23C

 

[Aiken Drum]

Biomax is what those microbes i mentioned lives on. Those microbes consume ammonia and nitrite and produce nitrate. It says on the box im looking at that it "reduces and controls ammonia and nitrite". Just check that on your packaging because you say nitrate.

Carbon isnt needed. It has very limited use and in most tanks it serves no purposes. You use it to clear water of tannins, clear medication from water after a course of treatment, and reduce odours. All of these issues are temporary after which you can remove the carbon once its done its job. Carbon only lasts 2 to 4 weeks before it needs replacing and is quite expensive to replace. Personally take out the carbon and use the space you free up in the filter to add some more biomax.

You arent over stocked and your filtration is sufficient. So we are back to something crashed your cycle or something is adding more ammonia than has been in there previously. Check around for any dead fish. Re-establish the cycle in the same manner you did previously. Keep on top of water changes until your cycle re-establishes.

Dont use stability. Of all the bottled bacteria products its probably the worst on the market. Dr tims one and only or tetra safestart are better products. Fritz #7 or #9 have good recommendations too.

 

[Ephuntz]

Thanks for the tips! I'll add in more biomax (I think i typoed Nitrate in that response). I have kept my eyes open for dead fish, I've been checking before I leave for work and when I get home. maybe I'll pick up tetra safe start or the other one you recommend and I'll do a series of 50% water changes until nitrite comes down.

 

[Ephuntz]

Update:

So I did 8 50% water changes and finally after 7 I noticed a large difference in nitrite levels... probably got down to 1 ppm or so I did an 8th change and dumped in the tetra safe start. I tested the water this morning an it seems like the nitrites are up to maybe 2ppm? it's hard to tell between 2 and 5ppm. when would I wanted to change water again if I just added the safe start?

Also, even with the new levels of nitrite my fish seem much much happier lol

 

[Aiken Drum]

If you have fish in the tank you really want it no higher than 0.5ppm.

 

[Ephuntz]

You'd suggest doing a few more changes then?

 

[Aiken Drum]

Yes. Unless you want to be back to extremely high nitrite in a few days. You could easily be doing 2 or 3 water changes daily for the next month or so.