Sudden ammonia spike in established tank?

  • We are currently upgrading MFK. thanks! -neo
honestly, its probably better to feed them pellets than rock, tiger or other shrimp that people eat.
 
swede;3128064;3128064 said:
honestly, its probably better to feed them pellets than rock, tiger or other shrimp that people eat.
Interesting. I never would've thought of that. If anything I'd have expected my shrimp to be better than what they get.


Last night they got a reasonable sized helping of pellets (eaten in a minute) and at 4am they were all breathing as heavily as I've ever seen them, especially the arowanas, and they were all freaking out. The lussoso was chasing the Aros, which is completely unacceptable. Now I have three nice black Aros with gashes in their fins.

Something is stressing these fish out and it's only for a period after feeding. (They are fine right now, 14 hours post-feed.) I guess if I lost some bacteria and am re-cycling it'd make sense that it could be nitrite, right? How quickly does the nitrogen cycle take to go from food to ammonia to nitrite to nitrate? It still seems odd that it'd be this stressful after a small feeding, even if all the bacteria was dead. And I still think it's very strange that all the bacteria in two FX5s would have died without an obvious cause.

Temperature is 80, pH is 7.5 as usual, ammonia is .25 at worst (I can't tell what color it matches, but it's definitely not darker than the green on .25), nitrates are under 10, aeration and flow are high. Looks like I need a new nitrite kit.

If I find a place that has prime will that help repopulate whatever I may have lost in my filters? Or do I need to just wait this out?
 
Prime is really just good for WC/emergency neutralizing of toxins. The bigger picture is that you need to do some more digging to figure out what the source of this is. Cycling, if that is the problem could take as long as a new tank. Though it seems that this happened over night and has no cause, there has to be a reason your levels would be off balance. And if your ammonia is truly only at .25 ppm, that should not be enough to stress the fish that fast. If you have no way of testing nitrites, that could be part of what is stressing out your fish. Once again though, we need to see why they would be spiking. High nitrites in an established tank shouldn't spike, especially without a reason.
 
have you noticed any change in temperature in the tank? do you have a heater? a drop in temperature can hurt the good bacteria, which in turn could make it too little for your bioload
 
even when doing a WC, if you add water that is colder than your tank temp, you can alter the tank temp relatively quickly, even if the tank is heated. I'm just racking my brain to think of anything that could've happened. I would increase WC to weekly and in the process really vacuum the gravel. Search the tank for hidden pieces of food or anything that could be dead. Even live plant pieces that are rotting can funk up your levels
 
The tank temp has never spent any time significantly lower than normal, but I do have 2 250w stealths that can only maintain about 78 despite being set at 83, which has always annoyed me.

During a recent water change I came back to find that the tap was running very cold (inconsistent tap from the tub I guess) so I had to crank it up to hot to compensate for that and stir and monitor it. Maybe that did it. It was cold water from the tap then hot.

Now I can't remember though if that was before this started or if it was one of the two the first day that I noticed it. If it was the previous change, that's probably the best bet as to how it happened.

I do WC at least weekly with deep gravel vacuuming anyway - that'd hardly be an increase. No dead or rotting anything, no live plants, nothing.

The only thing I can think of is that since the ammonia never gets too terribly high (that .50 time was the highest) and then decreases on its own is that it seems like there is still some functional bio media, but that some died off. So it's as if the bit that's there just can't keep up so there are spikes before things level off.

I just need this to get fixed. Obviously for the health of the fish but also because I need these filters at 100% for when I transition to the bigger tank. Need them to keep running and help the new sump get up to speed.
 
well maybe you should up WC to twice a week just to ease the ammonia/nitrates/nitrites and see if your tank levels itself out. have you checked the filters themself to see if maybe something is rotting or got stuck in it?
 
Woke up this morning to find one dead and two severely beaten black arowana. I'm furious.

I partitioned the tank and put the suspected villain by himself, but I've never seen the attacks so for all I know it's a different fish. This guy has never been a friendly fish but these Aros only started getting beaten up two days ago.

I'm in search of a 75g tank or something like that now, because I'd really rather pull the other two Aros out and keep them by themselves, just in case.

Doing a big 50% WC now and I took a lot of decorations out so that nothing can accumulate underneath.

This makes me so mad.
 
sorry to hear about your loss. have you checked the filters out thoroughly?
 
I'm about to disconnect the slower flowing one. It is slower than it was recently (before this thread) even though there was nothing in it last time. Not sure why it'd be so slow. I'll report if I find anything.

The Lusosso is mad at me for partitioning him. F him though. He's dead to me. About the only thing stopping me from feeding him to my dogs is that I have no proof since I never saw him attacking.

I guess I should be happy that this tank has been set up for 14 months now with only 3 deaths. But two were arowana, and all three could very likely have been due to attacks (the third was a datnoid who had an eye taken and jaw broken in an attack and only lasted 3 days after that). It's a sign of my growing experience that this ammonia/filter issue is all I have to deal with in May, as in previous years I have always had a plague of some sort when the weather outside heated up and messed with the environment. This year it's just a mystery filter bacteria death.

So far the other two aros seem OK. I still want to get them into their own 75 though if I can find one. I wonder if a 75g tank would fit in my 2 door car's front seat if I reclined it all the way (it has wide doors - no way it'd fit in the sedan).

Thanks for all your help and interest in this, by the way.
 
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