15 Fish Dead...

LolaLouie · Nov 9, 2008

A week ago I noticed my 4 pentazona barbs had white spot. I treated instantly with protozin. The white spot cleared up the next day. I continued the rest of the dose which i completed yesterday but the thing I don't understand is over the past 3 days my 10 cardinal tetras have died (no real symptoms, the last few have had slight fin rot), 3 hatchetfish (the only one i actually saw die was swimming round as normal then suddenly dropped to the bottom dead), and 2 of my bue tetras. What I'm confused about it:

Why are only my tetras and hatchetfish dying while all my other fish appear fine?

Why when the white spot cleared up almost instantly are the fish still dying a week later?

Why are the fish that showed symptoms of whitespot fine while the tetras who didn't even appear to have it are dying?

Also I was wondering when is it safe to add new fish to the tank? The outbreak of white spot was caused by introducing new infected fish.

Thanks :good:

Tolak · Nov 9, 2008

How about a little background info?

Tank size:
pH:
ammonia:
nitrite:
nitrate:
kH:
gH:
tank temp:

Fish Symptoms (include full description including lesion, color, location, fish behavior):

Volume and Frequency of water changes:

Chemical Additives or Media in your tank:

Tank inhabitants:

Recent additions to your tank (living or decoration):

Exposure to chemicals:

LolaLouie · Nov 9, 2008

Tolak said:
How about a little background info?

Tank size: 200l (50g)
pH: 7.8
ammonia: 0
nitrite: 0
nitrate: 40 (same as tap)
kH: hard
gH:
tank temp: 28 (but up to 30 since whitespot outbreak)

Fish Symptoms (include full description including lesion, color, location, fish behavior):

Slight fin rot, other fish in the tank had white spot, really sudden death

Volume and Frequency of water changes:
30-50% weekly

Chemical Additives or Media in your tank:
none
Tank inhabitants:
3 angelfish
5 corys
2 plecos
2 hatchetfish (were 5)
0 cardinals (were 10)
2 blue tetras (were 4)
4 pentazona barbs
1 bolivian ram
5 cockatoos (juvies)
4 adfs
Recent additions to your tank (living or decoration):
10 cardinals (all dead) 5 hatchetfish (3 dead) 4 blue tetras (2 dead)- all from different shops
Exposure to chemicals:
protozin medicine

backtotropical · Nov 9, 2008

Hi Gemma,

The first thing that jumps out at me in your post is that your tank is at 30C. Thats too hot for most fish and oxygen saturation will be seriuosly depleted at that temp. Your tank is quite heavily stocked too which won't help.

Protozin also hinders oxygen saturation so that will make things worse. I understand that you turned it up to treat the Ich, but did you add extra aeration to compensate?

Also, 28 is very high for normal average temp. Most tropical community tanks should sit between 24 - 26C.

Lastly, 19 fish is a LOT to add at once. Did you add them all on the same day?

Cheers

BTT