Tank crash! what was the cause?

[Hwom91]

My 90 gallon tank just crashed two days ago at my moms. Iv had it set up for a year.
My mom lives in town and has city water. My dad has well water so the surviving fish are fine.


One night i went to bed and everything was fine. The next morning all my cichlids were dead along with a couple pictus catfish. The only survivors were my ornate, sen, and angle fish. I checked the water and ammonia, nitrite, and nitrate were all off the charts. I did a water change and moved all the fish to other tanks at my dads. I checked the tap water and the ammonia was more than 8 ppm. Thats all the higher my test kit will read. I just checked my tank and tap water today and the tap is fine and my tank is off the charts again. I cannot figure out what is causing all this trouble. Any ideas?

 

[dangerhack]

i dont know the answer but im curious to hear what it could be?

 

[Ancient_Fish_Master]

what kind of filters are you using on the tank?

how long has the tank been running?

 

[ecoli73]

Did you change water before the crash? I suspect your biological filter is toast from whatever happened.

 

[tiddlywinks]

i think they ran out of air? you have any bubblers?

 

[ecoli73]

The tank was setup for a YEAR...I think the fish would have noted a lack of oxygen before the crash

 

[Owain4]

"I checked the tap water and the ammonia was more than 8 ppm."
Did you detoxify the ammonia in your water??? A single recommended dose will not detoxify ammonia at levels at that extreme, you would have needed to triple dose or x4 dose the detoxifier. What happened was who ever did a what change wasn't aware the ammonia levels increased and added it to the tank which caused ammonia poisoning in the fish. that level will kill most fish instantly. City water tends to get more ammonia in it after winter when all the water melts and washes chemicals into drinking water and rivers. was there a bad storm??? that would increase the levels slightly.

This same thing happened to me once, i added city water that was at 4-5ppm of ammonia and i didnt notice that it increased right after the snow melted. so when i added it to the tank my fish were showing signs of poisoning, which i was lucky to notice in time.

Hope that solves it.
​

 

[HyPHyISM42o]

sorry 4 ur loss

 

[tomojsg]

you gotta give us more info then that. like did you do a wc?
if yes then how big of a wc did you do, did you use water
conditioners/treaters? or did you not do a wc for a long time?
the more detailed information you give us the better ppl can help
you...

 

[Hwom91]

I did a 30% water change a couple days before. I do water changes every week and i always use water conditioner. I didnt know the ammonia was sky high until after the crash. I just happened to think about looking at my tap water to see if that had anything to do with it. Iv been using a rena xp3 on this tank since it was set up. I have a bubble bar going up the back of the tank so oxygen could not be the cause. If it was the tap water why would it take 2 days before the crash and not to have any signs is what is confusing me.