Fish Are Dying

[Brandenw]

Hi, I'm new and bought a 150 gallon used tank with established gravel and a small amount of water and fish when I transported it home. Everything was great and I filled it with 60 small community fish. Now 10 have died in 3 days. Petsmart said my ammonia was a little high but not too bad. No cloudiness but I did do 120 gallon water change 6 days ago because water stunk from the Gravel being so dirty from the previous owner. I just treated with stability and prime. Temp is 80. Have I done the right thing?

 

[Chad]

It's likely the gravel was full of detritus. Even rinsing it is not likely to clean it enough.
 
I really recommend replacement of the gravel with new.

 

[DrRob]

Ammonia is bad regardless of level. It's a sign that the biofilter isn't coping with the current load.
 
What's the filtration situation in the tank? Was the tank in use up until you bought it, and was the filter transferred with the tank without being dried out or left out of action or with no fish for any length of time?
 
Sadly the established gravel doesn't hold a huge amount of bacterial culture unless it was from an undergravel filtered tank, so although it'll help it won't solve the problem.

 

[Chad]

In this case I feel the gravel is likely the source of the ammonia. This is pretty common when old gravel is disturbed.

 

[Brandenw]

The filtration is 2 big aqueon quiet flows in which I just changed the filters on the first night. My water was pink and stinky 3 weeks later so I vacuumed really good as i changed out 120 gallons of water and a couple of days later fish started dying so I changed the filters now they are dropping like flies

 

[EllieJellyEllie]

Never change the filter cartridges. You just ruined the whole cycling process. You need to treat this like a fish in cycle at this point.
 
The filter cartridges hold the majority of good bacteria it needs to break down ammonia and nitrites. IF you change the cartridge then take the middle of it and some gunk and put it in the new cartridge

 

[Chad]

It really does sound like the bacterial filtration has been destroyed during the process of moving and resetting up the tank. Check out the article on cycling at the top of the site and perhaps it will help.

 

[Liv15]

Maybe you should sell the fish and start from scratch?

 

[Lunar Jetman]

I think daily large water changes immediately along with a test kit to measure the stats yourself. This will give you a fighting chance of keeping them. Reading up on the various links on here will help too of course. 

 

[Brandenw]

So, I have had all my levels checked at 2 different pet stores and there is no ammonia, nitrates are normal, and ph was about 7. Fish are still dying. 4 blood parrots are hanging out in a plant together an not moving. I'm lost at what to do next

 

[Chad]

What is normal for nitrates? Did the test show any nitrite?