Fish Dying Without Explanation

[backtotropical]

Hi, i have a 55gal Juwel tank set up as a community fresh water tank. All is going well until a few days ago. I came home to find one of my mollies dead. One of them was being bullied so put it down to that. Today, all my fish were fine, then about an hour later, one of my gouramis is dead. No sign of injury, suffering or disease, just seemingly quick death. I dont know why.

My water parameters are:

Ammonia NIL
Nitrite NIL
Nitrate 5ppm
PH 7.5

Stock is:

40 Neon Tetras
4 Dalmation Mollies (now 3)
2 Blue Gouramis
2 Red Gouramis (now 1)
7 Peppered Corys
2 Bulldog Plecos (just introduced a few days ago)

The only thing which has changed to my knowledge is the introduction of the plecos, but as far as i know, they are peaceful community inhabitants. I have never seen any aggression in the tank.

Help!

 

[Lhutch]

may have been the plecos,could have had something on them from the water,should always quarantine new fish,other then that not sure,ph is a little on the high side, but im sure its not that

 

[TylerFerretLord]

If I recall correctly, neons and gouramis like a lowe PH, but that doesn't explain the molly death, as they become very hardy at higher PH levels.

Well, since you have no clue what happened, can you give us the following info?

Temp
Food fed
Do you use spray cleaners or anything in a pressurized can?
Did you recently paint a room?
What did they fish look like when they died?

 

[Musho3210]

i wouldnt worry about Ph, 7.5 is fine for most fish, unless you want to breed them or something.

 

[backtotropical]

Thanks for the replies.

Temp 26c
Food A mixture of Tetra Prima, Flakes, Tetra Plecomin Tablets and live brineshrimp, fed on alternate days.
No cleaners or sprays used.
No painting recently.
Fish looked normal. No sign of injury or any disease.

I am confused!

 

[Scotch_Egg]

the temp is a little high, but nothing to write home about. might be natural causes. take a water sample down to your lfs and they might beable to test for causes.

 

[Lhutch]

maybe one died out of the blue and his friend killed himself?(herself)

 

[backtotropical]

I cant think of anything my LFS could test which i haven't already tested.

Anyone else have any thoughts? No more deaths, but i'd like to get to the root of the problem to stop it happening again.

 

[-germ-]

Was it the gourami bullying the mollies?
They are notorious for not getting on......
Had the molly been nipped at all or scavenged in death?
How old is the tank, did you buy it new or second hand?

 

[backtotropical]

Hi Germ,

I have never seen the gouramis being aggressive. I think they have enough space and hiding places to each claim their own territory, as i am aware of their reputation, and so keep a close eye on them. I did see one of the other female mollies bullying but that was all.

The dead molly had no signs of having its fins nipped or being scavenged after death, nor did the dead gourami.

The tank is about 4 years old. I bought it new and kept red-bellied piranha in it first of all, it was then a reef tank, and has recently become a freshwater community. It has been well cleaned out between changes.

 

[CruX]

Hi Germ,

I have never seen the gouramis being aggressive. I think they have enough space and hiding places to each claim their own territory, as i am aware of their reputation, and so keep a close eye on them. I did see one of the other female mollies bullying but that was all.

The dead molly had no signs of having its fins nipped or being scavenged after death, nor did the dead gourami.

The tank is about 4 years old. I bought it new and kept red-bellied piranha in it first of all, it was then a reef tank, and has recently become a freshwater community. It has been well cleaned out between changes.

I am certainly no expert, but I would put it down to 'one of those things'. I quite often see your posts on here and you come across to me as some one as very knowledgable to the point where you are one of the first people I would hope would respond toa question or problem I had. I think if it was a big problem you would have spotted it. No more fish have died and nothing seems wrong, perhaps they were weak fish and it was inevitable. I once bought fish from a shop I was told to avoid as the fish are prone to popping their cloggs without warning, indeed one died overnight, I was convinced something was wrong with my water even though all the stats were spot on and the fish were thriving, my better hald came home with a pair of Chocolate Gouramies and I was convinced they wouldn't make it but they are thriving and look wonderful, I can't wait until the fish I am growing out for my Mother are big enough for her tank as then I plan to buy about 8 more.

On the molly front, We used to keep mollies before we knew they prefer a bit of salt and a few of them died for no apparant reason, a friend also bought some with a view to adding salt, he planned to change the salinity gradually, he went out and bought the salt and came home to find half of them dead, whereas the other live bearers he bought survived. Puts me off mollies lol,

 

[backtotropical]

Thanks Crux,

You are very kind. Maybe it's 'just one of those things', i don't know. I'd really like to get to the bottom of it though. Maybe i never will.

Thanks for your reply.

 

[CruX]

Its a pain not knowing isn't it? I reckon if nothing else happens that it was just their time to go.

 

[Squidman]

It was probably the plecos picking on his/her tank mates!

 

[TylerFerretLord]

It was probably the plecos picking on his/her tank mates!

To my knowledge, plecos are only agressive to each other, and it's not like they could bite.