One Dead Fish, One Dead Shrimp

[Lizzie71]

This morning we had one platy and one amano shrimp dead in the tank (the sig below shows stocking before these died).

Tank stats:

Ammonia 0
Nitrite 3
Nitrate about 20
Temperature 27

Other fish appear fine at the moment. I've already done a 50% water change.

No recent additions to the tank - the guppies and shrimps went in a month ago. Soon after that, I treated the tank with anti-bacterial medicine as I had a sick platy. This was not the same platy who has died.

Sadly the fish we lost was my 7 year old son's first ever tropical fish and he's really upset. RIP Francesca

I know this might sound silly but I wonder if this has been caused by cucumber. I left a piece in for 24 hours by mistake and when I fished it out yesterday evening, it had disintegrated quite badly. I tried to get it all out, but there were still a couple of small pieces floating when I did the water change today. I am now pretty sure it is all out. Could this cause the nitrite spike?

The worst thing is that I was going to use some of the filter media from this tank to seed a new tank - now I think I'd better wait until I'm sure everything is OK with the first tank.

 

[Miss Wiggle]

any decomposing plant or animal matter can cause a nitrite spike so yes it could well have been the cucmber that did it.

the other possible culprit is the antibacterial med, it's designed to kill off bad bacteria, but they often wipe out your filter bacteria colony as well, have you tested regularly since using it? You may have not seen an ammonia spike which has now passed but the exposure to ammonia and now nitrite has done for the fish.

either way, do some big water changes and monitor the levels daily until they stabilise. and no, you'd best not seed another tank from this right now. let the levels stabilise then give it a monbth or so for the bacteria colony to build up to full strength. if you remove some media from a newly cycled tank (which yours may effectively be if it is the meds that did it) then it may cause another cycle.

 

[Lizzie71]

Thanks for the quick reply. I haven't tested for a couple of weeks to be honest, so I guess I could have had an ammonia spike. I'll do as you said re water changes etc.

I can't wait a month to start my new tank, it's all set up, just waiting for fish

 

[Miss Wiggle]

well i know it's hard but you just might have to, other alternative is to do a fishless cycle on the new tank.

without previous water test results it's impossible to say if it was the meds or the cucmber, both are possible candidates, and without knowing you can't make an assumption that the bacteria colony is strong enough to withstand part of it being removed to seed another tank.

just for future reference, you should always test the water daily for a week or so after adding antibacterial meds to make sure things are stable.

 

[Lizzie71]

Do you think adding bactinettes to the existing tank would help to get the cycle back in kilter more quickly? I need to go to Maidenhead Aquatics today anyway, so I could get some.

 

[Miss Wiggle]

yes it could well do, again though it depends if the nitrite spike is due to the cucmber or the meds

if it's the meds then you're tank is cycling again which means adding bactinettes should help.

if it's the cucmber then you're tank isn't cycling, it's just not quite dealing with the extra waste produced, so the media should be ok and therefore you don't need bactinettes.

again without knowing what the readings were over the last few weeks you can't tell which it is and consequently don't know if bactinettes really will help.

my inkling however is that it's the meds not the cucmber, however that is just gut instinct, not based on any fact whatsoever.

 

[Lizzie71]

My gut instinct is the meds too - the cucumber incident was only yesterday and I don't think that it could have killed the fish so quickly. I think I'll give it a try - I won't really lose anything I guess

 

[Miss Wiggle]

exactly, i think the meds is probably the more likely cause. The cucmber is theoretically possible, but i think less likely to cause such a big problem.

adding bactinettes shouldn't do any harm, obviously finances permitting but if you feel that the levels have stabilised in a week or so on this tank, you could add a smaller amount of media than you usually would to seed to the new tank, then add bactinettes to both tanks to give the bacteria colonies a boost. risky but it might work out OK!!!!

 

[Lizzie71]

Brilliant, thanks for such good advice. You're a star

 

[Miss Wiggle]

no problem.

 

[Lizzie71]

Maidenhead Aquatics don't stock bactinettes any more And my nitrite was still sky high after a 50% water change, so I did another 50% change this afternoon. I think it's going to take a few changes to sort this out.

I got the plants for my new aquarium anyway, even if I can't add fish just yet!

 

[Lizzie71]

Sadly we lost one of our two male guppies this morning. Nitrite is still sky high despite water changes.

All the fish look miserable, and I don't blame them.

I think the problem may be the filter. The flow coming out of it is a pathetic dribble - I've taken it apart to look for blockages but nothing obvious. I am wondering whether to buy a new filter and transfer the media over? The one I have is a Fluval One which came with the tank.