Bacteria Died

[AquaAndy]

Last week I woke up to find most of my fish dead, while the rest of them swimming along the water surface gasping for air. I immediately did a water test to identify the problem. While my ammonia and nitrate levels were around normal, the nitrite was 1-2ppm. I removed the dead fish, give the substrate a good clean, changed 50% of the water, and added additional Prime to control the remaining nitrite. I monitored the water for several hours and found the nitrite was spiking again so changed out another 50% of the water. While I did this I opened up the canister filter to give that a clean and found a slime all over everything. I'm not sure what it was but it was black/green, thick, and oily. The bio-media was covered in this slime so I rinsed it in used tank water to clean them up and put the canister back together. Since then the nitrite has been fine, but the ammonia has been shooting up everyday. I have been changing 50% of the water and adding AmmoLock. Yesterday I purchased a few plants in hopes they would absorb some of the ammonia being produced.

I tested my water again today and found this...
Ammonia: < 0.05
Nitrite: 0.05
Nitrate: NILL

I guess adding the plants was a good idea because they appear to have controlled the ammonia. But I guess all my canister bacteria has died?

Any idea what caused the Nitrite spike?
I assume since then all my bacteria has died?
How much ammonia do plants actually absorb?
Does AmmoLock actually work?

 

[techen]

You've decycled your tank. How long have you had the tank for?

 

[AquaAndy]

18 months or so.

 

[techen]

Thats strange to have a sudden spike of nitrite. Anything you did different.

 

[AquaAndy]

Nope, nothing comes to mind.

 

[AquaAndy]

I've just had a thought..... If the water lacks oxygen, would that in theory kill the bacteria?

 

[N0body Of The Goat]

With that sort of nitrite reading you should be changing ~95% of the water, it messes with the fishes' ability to get oxygen out of the water, until you find the true root cause of what caused the dangerous spike a 50% change with Prime is risky.

The bacteria do need oxygen and if they are multiplying in response to a massive increase in food source (eg. from decaying food or a substantial addition of new fish to a tank), they will consume a lot more oxygen at the expense of leaving enough for the fish.

After such toxin spikes it is important to provide extra water surface movement, even after the big water change, to ensure the bacteria colony can expand and still leave enough oxygen in the water for the fish.

 

[AquaAndy]

My water had little or no oxygen in so I'l stuck a massive airstone in there and left it blasting away overnight. How long does it take to oxygenate the water? I have also rearranged the filter output to make more water movement so to avoid this problem again.

The substrate was spointless so I don't know what caused the spike in the first place.

 

[AquaAndy]

My API NH3/NH4 test kit is showing a reading of 2ppm.
My JBL NH4 test kit is showing a reading of 0ppm.

When changing my water I have been adding AmmoLock and Prime.
I am guessing the ammonia present in the tank has been ionized into a non-toxic form?
If so, shall I leave it alone or continue changing out the water?

 

[balajake]

What kind of substrate do you have ?

 

[N0body Of The Goat]

My API NH3/NH4 test kit is showing a reading of 2ppm.
My JBL NH4 test kit is showing a reading of 0ppm.

When changing my water I have been adding AmmoLock and Prime.
I am guessing the ammonia present in the tank has been ionized into a non-toxic form?
If so, shall I leave it alone or continue changing out the water?

Prime will only detoxify a certain amount of ammonia for upto 24 hours, depending upon the doseage (upto 5x standard is safe, 25ml per 200l) and what other things are in the water that Prime deals with (nitrite, nitrate, organics).

What pH is your tank water? In alkaline conditions, 2ppm ammonia could be lethal and need a massive ~95% water change.

 

[balajake]

I agree massive water changes are your friend. If I were you I'd be looking into whether your substrate has gone iffy with gases or something rotting in it. Might be time to change it to fresh.

 

[daizeUK]

My API NH3/NH4 test kit is showing a reading of 2ppm.
My JBL NH4 test kit is showing a reading of 0ppm.

When changing my water I have been adding AmmoLock and Prime.
I am guessing the ammonia present in the tank has been ionized into a non-toxic form?

NH3 is toxic ammonia. NH4 is non-toxic ammonium.

While I did this I opened up the canister filter to give that a clean and found a slime all over everything. I'm not sure what it was but it was black/green, thick, and oily. The bio-media was covered in this slime so I rinsed it in used tank water to clean them up and put the canister back together.

I'm intrigued by this dark slime you mentionned, it sounds significant. I suspect you may have an infestation of bacteria, mould or algae which is causing the slime. I have read that heterotrophic bacteria can leave a white slime which reduces available surface space for nitrifying bacteria. Your slime is black not white but it sounds like it may have a similar detrimental effect.

I would suggest you do a google search on black slime in aquariums, there are a few articles about algae and similar, perhaps you will be able to identify what this stuff is in your tank.

 

[AquaAndy]

I'm using the Eco-Complete substrate, and it appears pretty clean.
The black slime has now completely gone but I suspect all the bacteria has died off.

Either way I have added AmmoLock into the tank which should ionize the ammonia and added SeaChem Stability. Tthe strange thing is there is no sign of any Nitrite yet after several days. I thought Stability was a live bacteria which should start working almost instantly to convert the ammonia. Will the bacteria consume NH4 or just NH3? If just NH3, then this might explains why I have no Nitrite.

 

[AquaAndy]

I've just done another water test and got these results...
Ammonia NH4 was still showing 0
Ammonium NH3 was showing 2ppm
Nitrite was showing 0
Nirtrate was showing 0

I have since changed 90% of the water in two goes.
I've also done a mega clean of the substrate and filter.

I will continue to add SeaChem Stability but I am starting to think its not doing anything.

Many forums say I don't need to have an airstone in the tank as long as there is sufficient water surface movement. What is sufficient water surface movement? I took a little 20 second video on my phone, so you could see if this is okay? Its on Dropbox http/db.tt/lbx2er1y