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[bonzo]

Iknow this is the wrong place to post this but I cant get a reply in the emergency section. The story is.




I,ve had some unexpected deaths in my tank this past few days. I,ve tested the water with a liquid test kit and its fine. Details are below. I,m baffled.

Tank size: 350 litre
pH: 7
ammonia: 0
nitrite:0
nitrate:0
kH:
gH:
tank temp:28

Fish Symptoms, Generally at start they just arnt themselves if you know what i mean then they start swimming into things looking a bit delerious, hanging around the top of tank then sinking. then lying on bottom of tank for ages then going crazy trying to get to the top and sinking tail first then dying. Nic took 3 days to die and young rotkeil went within 24 hours. No other fish showing symtoms yet but there was a 2 day gap between the 2 dead fish.

Volume and Frequency of water changes: 50% weekly

Chemical Additives or Media in your tank: fluval internal

Tank inhabitants: two six inch rotkeil, two 2 inch rotkeil (1 now dead), two 1 1/2 inch GBR one 2 1/2 inch nicuraguan (now dead) and 5 cardinals

Recent additions to your tank (living or decoration): cardinals but they seem fine

Have been doing a wc in tank everyday since saturday.

 

[markandhisfish]

are you sure thos test results are right? you shouldnt have 0 nitrates

 

[kaivalagi]

Did you do a liquid test before you went into water change overdrive? Could the small internal filter not really be handling the bio load for the amount of fish you have? I have 2 external filters running on my 100G

Could it be stress related? The 2 fish that have died were quite small and assuming your tank is a Trigon 350 corner that 350 litres doesn't give the best line of sight distance to help with territories etc

No continuing symptoms with the other fish either....I'd say sit tight and watch your fish carefully.

Also it might be worth taking a reading for stats before a water change to see if any of the levels are too high for a 24 hour period, if not then maybe skip the water change and re-test the next day...just so you know what the situation is with your tank and to make sure you haven't got a mini-cycle occurring....

are you sure thos test results are right? you shouldnt have 0 nitrates

Exactly my thoughts, hence asking about testing before a water change

 

[bonzo]

are you sure thos test results are right? you shouldnt have 0 nitrates

All our tanks are well planted and never have nitrates in any of them.

 

[bonzo]

Did you do a liquid test before you went into water change overdrive? Could the small internal filter not really be handling the bio load for the amount of fish you have? I have 2 external filters running on my 100G

Could it be stress related? The 2 fish that have died were quite small and assuming your tank is a Trigon 350 corner that 350 litres doesn't give the best line of sight distance to help with territories etc

No continuing symptoms with the other fish either....I'd say sit tight and watch your fish carefully.

Also it might be worth taking a reading for stats before a water change to see if any of the levels are too high for a 24 hour period, if not then maybe skip the water change and re-test the next day...just so you know what the situation is with your tank and to make sure you haven't got a mini-cycle occurring....

are you sure thos test results are right? you shouldnt have 0 nitrates

Exactly my thoughts, hence asking about testing before a water change

Not a corner tank. its just plain rectangle. Its an old tank with no name on it.
Tests done before water change. I realise the filter system wont be good enough if all the fish are kept in it long term.But we,ve been keeping a close eye on stats. Thought ourselves the nic might be getting bullied and put it in quarantine tank but then the little rotkeil died.

 

[kaivalagi]

Can we see a pic of the planted tank and the filter?

I can only think of these as possible causes:

• Mini-cycle due to filtration being inadequate - solve by getting more media capacity and flow
• Mini-cycle due to chlorine or other issue that killed off bacteria - solve by rebuilding the bacteria colony up and use interim media too
• Stress related deaths from territorial disputes, you do have 2 big rotkeils in there
• Bacteria/Viral infection with fish...but only 2 affected so unlikely

I might just be worth taking a water sample (post 24 hours without water change) to an LFS for testing, to get a second opinion, maybe your liquid test is no good?

 

[markandhisfish]

that lot pretty much covers it really , cant think of anything else it could be , unless the new cardinals have bought something in with them

 

[bonzo]

I'll get pics up later have to leave soon as have fish to deliver. Will take water sample to lfs and get it tested. The one thing we done different was started using seachem prime at water changes. Never seen large rotkeil bullying but one of the young rotkeil is a pest.

 

[markandhisfish]

the change to prime wont have made any difference .

 

[bonzo]

No photos yet waiting for batteries to charge. Got water tested and everythings fine. Will just keep a close eye do no water changes and test again tonight.

 

[Curiosity101]

When you switched to prime did you read the bottle and adjust the amount you were using? I know it sounds ridiculous and I'm assuming you did. But just on the off chance that you didn't thought I'd ask. It's unlikely it'd have an effect at all, but if you overdosed on prime then I guess that could be a cause.

And have you doubled checked your test kit is in date. I know you say they're well planted and have never shown nitrates... but equally if you have a duff nitrates test or test kit is out of date then what you think is no nitrates cause of plants could actually just be an incorrect test result...
Perhaps test your tap water as hopefully that will have nitrates in it, and if you already have done then fair enough the test kit is fine. It's just another thing worth ruling out if you haven't already.

 

[saz326]

Am thinking its NOT a water quality problem coz the cardinals would have dropped first - In my experience they are not the hardiest of fish.

At the same time I am wondering whether you may have overdosed the Prime and set off a mini cycle. (the bacteria in your filter feed off Ammonia and nitrite - Prime at a higher dose converts ammonia into another molecule which means the bacteria would get less food and die off)

 

[bonzo]

Definitely didnt overdose on prime. Reason we got it was because you used a lot less and we,ve 5 tanks running so was cheaper in the long run to use it.

We also couldnt understand how the tetras and GBRs survived if it was a water issue.

Also got water tested in lfs and its fine. No nitrates. Havent checked tap water

 

[markandhisfish]

to overdose dechlorinator you would have to use huuuuge ammounts of it . you can safely rule that 1 out . i agree if it was a water issue id expect the cardinals to be dropping like flies

Am thinking its NOT a water quality problem coz the cardinals would have dropped first - In my experience they are not the hardiest of fish.

At the same time I am wondering whether you may have overdosed the Prime and set off a mini cycle. (the bacteria in your filter feed off Ammonia and nitrite - Prime at a higher dose converts ammonia into another molecule which means the bacteria would get less food and die off)

prime at a higher dose converts ammonia into ammonium , which is less toxic to fish but can still be processed by the filter , using a big dose of prime wont cause a mini cycle

 

[kaivalagi]

I use prime and always use a dose a little over what is required, as I use a syphon/hose for water changes I dose for the whole tank volume not the replacement water and use 2 full caps for my main tank which is more like 370L than 400L...and 1 full cup for a 125L tank

Could you have under dosed with prime maybe? And killed the bacteria off a bit as some chlorine remains?

Clutching at straws here really...

Have you left the tank 24 hours and taken Ammonia/Nitrite/Nitrate readings yet?