Fish Just Dying

[blinky]

A couple of weeks ago I redid my tank after moving it - it's a 200l Juwel bow front and is well stocked but as well as the internal filter i have an external Eheim Pro filter (Which is new).

This was around 3 weeks ago but last week I added some new fish and they died, since then I have had at least one fish die each day, a lot of these are well established, one minute they are fine, an hour later they are dead! I did a water change on Friday and a 40% one a few hours ago, then I found a cherry barb on his way out. I have had the water checked by 2 different shops and both say it's perfect.

I am at my wits end as I just dont know what to do next. Would another water change do any good? 40% about 4 hrs ago and I do another 40% now?

 

[blinky]

Looks like the gills may be red - does this give any clues?

 

[Noahs ark6]

what is the capacity of the internal filter?

 

[Rogue4Fish]

do u not have a home testing kit for yourself? whats perfect?

with the new external did you use old media?

 

[blinky]

I dont have a home testing kit, the internal filter is the one supplied with the tank so I assume it should be able to handle 200l. The external one is just an addition to make sure the water is perfect.... When I moved the tank I kept the same filter media (and it should have still been wet) but it was a brand new external filter. The shops say, Ph, Nitrite, Nitrate and ammonia are all perfect, i.e. zero

 

[blinky]

OK, I got hold of a test kit and the results are in.....

Ph 7.6
Ammonia 0
Nitrite 0
Nitrate 80 - maybe higher but now as high as 160

So..... Dont know what to do about the high Ph but Nitrate indicates the end of the cycle and water changes should bring that down. Offski now to do another 10% water change, or should that be 20%?

 

[blinky]

Just tested the tap water as well and that is sitting at Ph 7.6 the same as the tank.....

 

[blinky]

I cleaned the filters (in tank water) and replaced about 5-10 litres, as I used that water to clean the filters. Now 2 hrs later the Nitrate is around 40ppm, maybe slightly less actually. I think I maybe put too much of solution 2 into the test the first time round? Obviously the filter clean/minor water change will have done some good as well.
Also went to the Pet Shop and the guy there said it may have been the clown loaches they sold me last week were carrying bacteria so gave me a bottle of stuff for free, it's now in at half strength as well. No losses today so far either......

 

[Kelly-Jo]

I had a similar problem a few months back, which I never really got to the bottom of. All of my fish were completely fine and healthy until I added 2 new fish to the tank which immediately seemed unwell and inactive. Both those fish died within about 3 days of each other and then a bronze cory and widow tetra followed pretty soon after. I'm still not certain but I think it may have been some kind of disease from the fish which were added which didn't appear to show any visible symptoms. Maybe if you added the clown loaches which were carrying bacteria of some kind, it affected the other fish? Do you have access to any kind of quarantine tank? As if this is the problem, in future this could be an option before adding fish to your main tank.