Whats Wrong With My Filter?

[Rorie]

I have two small filters, both for 20L tanks. I kept them in my main tank during fishless cycling. Once i finished that, i put them both in my QT which is 25L. I then fishless cycled that and all was well.

I then added fish and they were fine. As its a small tank, i tested it daily for ammonia which was always 0ppm. One day (about a 4 days in) the ammonia spiked! I got the fish into my main tank ASAP and they were fine.

So i left the QT to process the ammonia (dark dark green!). A week later and its still not processed it! So i did a 95% water change (given the water i couldnt get out!) and after a while tested amonia. IT was light green. I figured i'd let it process that, then start adding ammonia again and hope it did it quick. Well, 3 days on, and it is still lime green!

Both filters had mature filter in them. Both were in my main tank during cycling. Both then did their own cycle. Both are capable of running a 20L tank. But in a 25L QT tank they are not processing the ammonia!

I have bumped up the heat, got an air pump in there..... it does not make sense! Suggestions?!

 

[snowflake311]

Too many fish foe too little bactiera. You need to use more mature media or add less fish.

I would add more mature filter media to the tank and add some mature tank water. Then see if that helps after an hour or 2. If the extra media works slowly add fish to the tank. Then all should be fine.

 

[Rorie]

Well its just for my QT.... so no fish are in just now. I have a tiny amount, maybe 1ppm of ammonia, and after 3 days it has still not processed.....where as before the media was processing 4ppm in 24 hours. it has always been in ammonia filled tanks, but seems to have just died!

 

[snowflake311]

Was this filter left with out any food for the bacteria any long amount of time?

If you ran the filter with mature media in an empty tank for a day or more the bacteria might have died.

 

[Mikaila31]

what type of dechlor are you using?

 

[Rorie]

Nope, something strange has happened. Fishless cycled, added fish, got second ammonia spike, moved fish, tried to let filter process the remaining ammonia, week later it still hadn't processed it, so got rid of 90% of it, the remaining left about 0.5ppm, but 3 days on, it still aint processed even that!!

I use sera dech.

 

[Mikaila31]

Nope, something strange has happened. Fishless cycled, added fish, got second ammonia spike, moved fish, tried to let filter process the remaining ammonia, week later it still hadn't processed it, so got rid of 90% of it, the remaining left about 0.5ppm, but 3 days on, it still aint processed even that!!

I use sera dech.

I am not at all familiar with that. Some dechlors/conditioners can effect test results. But if you use it in another tank that tests fine its probably not an issue.