Newly Acquired Fish Dying

[mark4785]

Hi,

The dirty filter option is the only possibility. I didn't think a filter could be made dirty after pure ammonia introduction. I thought a dirty filter was one that is clogged up with faeces. I did inspect the filter interior yesterday and there were no smells or sign of dirt build up.

 

[WILDER]

I agree with you.

How are the black neons?

 

[mark4785]

I agree with you.

How are the black neons?

They are all eating and swimming as normal in a shoal.

i'm going to go and do that 50% W/C, filter clean, gravel vac and a bunch of o2 tests on the problem-tank. I'm a law student and should have been working through a massive reading list tonight but oh well

 

[WILDER]

My son did a 3 years uni course in Law.
Good Luck.

Let us know how you get on. That's if you don't mind.

 

[mark4785]

My son did a 3 years uni course in Law.
Good Luck.

Let us know how you get on. That's if you don't mind.

Thanks. The course is great at the moment but when tank/pond related issues arise I find I can't concentrate at all on academia.

I tested the O2 levels of the tank again before the W/C. Still got the 2 mg/l lethal result.

I decided to do a 100% W/C and I removed all of the filter media from the filter system. The base of the filter system is covered with yellow pieces of slime and some of this had broken away onto the lower filter sponges. I've removed all of this from both the base of the filtration system and the filter sponges. I think this is the stuff that may be using all of the o2 up.

I'm going to put a aeration 'bubbler' into the tank and re-test the o2 level tomorrow. Probably to dangerous to put any fish in at this stage as I have no idea where the o2 levels will end up in the next few hours.

 

[WILDER]

Have you tested your o2 levels.

 

[mark4785]

Just thought I'd update interested reader's as to the o2 levels. It's not great news.

On the 16th of October I re-tested the o2 level and it was between 2 and 5 ppm using the Tetra O2 test. So it has improved slightly but when you consider that my co2 filled aquarium (to the left hand-side of this problem aquarium) has an o2 level of 8 ppm, you know there's something up.

There appears to be a white film in the water column (looks like loose skin) and it is also in the base of the filter system. Attached below are images of it:

I guess the only resolution to this is multiple 100% W/C's and lots of filter scrubbing (no chemicals and tap-water involved of course).

 

[WILDER]

I would maybe think about starting a thread in your new freshwater tank section of the forum. So members can offer advice.

Thank you for the update.