Bala Sharks sudden death

Drat, dang, and lots of punctuation. Night before last, I was admiring
our Balas. How they've grown, how healthy they look. Skipped morning
fish feeding while hurrying to get myself to another appointment. Last
evening, one Bala swimming around still looking quite healthy and happy,
though quite alone. Three dead Balas floating. One Bala missing
entirely!!

Surviving fish still seems quite normal. Dead fish, well it's hard to
tell after they're dead (duh) but the gills didn't look damaged, no
obvious damage elsewhere on the fish, no bloating. Just... floating
upside down, dead.

120 gallon tank
2 Emperor 400 (biowheel) filters
no detectable ammonia
no detectable nitrItes
nitrAtes 40 ppm
pH 7.6 and stable
temperature 78F and stable

20% water change weekly; last water change the day before the die-off.

Tankmates: 5 juvenile Bala Sharks (now one)
11 Tiger Barbs (all look and act normal)
1 Liposarcus pardalis, common pl*co (picture of health and asking
"where's the squash?")
3 Striped Raphaels (one found, big and healthy; two not seen but
presumed to be fine; and yes, Raphael cats are like that)

First thought is of course contamination or bad water change. But only
the four Balas were affected! We dechlor water before adding.
Contamination, I don't see how but has the same problem, only these fish
seem to have been affected. Can't find a dissolved oxygen test but with
two filters and the bubbler, shouldn't be a problem; also, no signs of
respiratory distress in any other fish (nor in these fish the night
before!).

ANY ideas? I've tested ammonia two ways and am now taking a sample of
what my tests say is pristine water to the lfs to see if their tests say
any different. Sure would love to know what happened and if it can be
prevented from happening again.

I wouldn't mind knowing where Bala Number Four went, either -- we've
checked around the tank for fish jerky, though there aren't any big
holes for jumpers, and found nothing. However the Raphaels are
protien-loving scavengers and I wouldn't put fish fillet entree beyond
Tess the common plec either. So that may not be a complete mystery.

Wail! Sob! Alas, alack, and WOE! what happened to my beautiful
Balas?!?!?


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Only know that there is no spork.

On Thu, 26 Aug 2004 13:18:35 -0500, Elizabeth Naime wrote:
Three dead Balas floating. One Bala missing entirely!!

Oh dear

Surviving fish still seems quite normal. Dead fish, well it's hard to

Balas are quite sensitive, the others you are keeping aren't.

They could be the first indicator of a problem, like a dead
canary in a mine told the miners their air was bad...

ANY ideas? I've tested ammonia two ways and am now taking a sample of
what my tests say is pristine water to the lfs to see if their tests say
any different. Sure would love to know what happened and if it can be
prevented from happening again.

If your tests are coming back ok, it's hard to know. I've suffered this
(although none died they did get sick) and I do sympathise.

You say there is nothing poisonous etc. but are you home with the
tank all day? My own fish suffer every time they boil tar in the
road outside or the building site out back, you don't have to
cause a problem yourself for there to be one.

If I was you I would
a) do a large water change including gravel vac
b) add fresh carbon to the filter in case there are any poisons
c) oxygenate as much as possible (extra airstone etc)

and keep a close eye on them all :-(

Another thought - could there have been a temperature change?
Heat of the sun at midday, or quick power outage?
Or might the filter have stopped in a powerout, gone anaerobic,
and dumped toxins when it came back on?

You may never know the cause, but I wish you luck.
I know that it's very frustrating!
--
Flash Wilson
-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-
A. Because it breaks the logical sequence of discussion
Q. Why is top posting bad?

Update: pet store test confirmed my results. Different test types and
brands... I must admit that the readings are correct.

I definitely worry about contamination from something. We're usually
very careful, though. I'll have to look into things that might happen
while I'm out, as you suggest.

Considering that I just did a 20-25% change the night before, which I
think is considered "rather large" for tropical tanks, would another
water change be insurance or just stress?

Definitely I'll put in some fresh carbon, something I hadn't thought of.
And I can get a second bubbler in there as well; I don't think there's
any problem with the aeration but under any stress, the more aeration
the better.

In further news, the surviving Bala and the Tiger Barbs seem fine. I may
never figure it out, but I hope I find out if it's preventable. I will
need to put more Balas in there once I know it's safe, won't I? We got
five when we started because all sources I checked say they're social
fish who do best in company.

*sigh*
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Only know that there is no spork.