# Fish dying off......dirty filter?



## bailey0789 (May 15, 2010)

Earlier today I had about 6 dead fish in my tank. I had been pretty lax in cleaning my filters because they were good for a long time. I was vacuuming at least once a week. After i found the dead fish i checked the filters and they were really bad. Im guessing this is the cause because about a year ago I had the same thing happen when there was a couple dead fish hidden and they were rotting and I figured they contaminated the water. I did a big water change and cleaned the filters and the water looks great. But I just watched one of my baby mollies shut down and settle at the bottom. I took her out and put her out of her misery. is there something else I should do? Im just hoping I dont wake up tomorrow to more dead fish.


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## Barbman (Jun 17, 2011)

What are your water parameters? Ammonia, Nitrite, Nitrate and pH? What type of filter do you have? By dirty I assume you mean the filter media was full of gunk? If so, then just give it a quick rinse in aquarium water.
The filter media is where a large number of Beneficial Bacteria live and unless the filter media is literally falling apart, you do not change it.

Changing the filter media can bring on a mini-cycle leading to a buildup of Ammonia. The first step is to get your water tested, I recommend using the API test master kit. Once we know the number we can better assist.
For now do your fish look like their breathing rapidly, red gills and or are they hanging out near the surface?
If so these could be signs of ammonia poisoning and or low oxygen content. Consider at least a 50% water change. From then on let your water test dictate how much water to change.


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