Fish Death

[jackaddict]

Hi guys, I am hoping someone my have some insight to why our fish die all the time.
The most common event is after a water change, the fish (not all) will start to show signs of swim bladder problems and a day or two later they will be dead.
We check all the usual readings and they always seem fine, though our water is rather hard and the PH is a little up, but the other levels are OK.
Fish we have lost in this manner are as follows.
Varying different types of Cory's, Clown loach's, Neon Tetra's and Guppies (the Guppies were in a different tank.)
It has actually got to the point that we are thinking of starting again from scratch as there might be something in the tank, but we just don't know.
Any thoughts would be appreciated.

Regards

Alex

 

[white9870]

what water conditioner are you using when doind then water changes?

 

[alihar]

What are your exact readings for ammonia, nitrite, nitrate and ph?
How much and how often so you do a water change?
Compare your tank ph reading to that of water straight from the tap and left to stand for 24hrs.

As White has already asked which dechlorinator are you using?

 

[TropicalLad21]

As well as what the above 2 posters have put if it's always after a water change it could be the temp of the fresh water and how quickly your putting it in the tank... are you making sure the fresh treated water is the same temp or just about?

When adding the water are you putting it in slowly or quite rapidly?

 

[This Old Spouse]

Are you using ANY dechlorinator/ conditioner?

How long has your tank been running? How big is the tank?

 

[the_lock_man]

As well as the thoughts of those above re chlorine, temperature, I am wondering about pH, GH, KH as well.

If you have something in there which radically alters water chemistry (eg lots of bogwood, peat in the filter, coral sand), changing a large amount of water may be shocking the fish.

It might be worth trying two smaller water changes per week.

Or, another thought, do you change your filter at w/c time? That's another common cause of such problems.

 

[jackaddict]

Hi again, thanks for you ongoing help.
We have 2 tanks - a 180 litre and a 60 litre. The Larger one has been set up for about two years now and this has been an occasional but ongoing problem since fairly early on. The small tank has been set up around 8 months and we have just recently had a death there as well, hence the post. Readings are: NO3 - 0, NO2 - 0, GH - 16, KH - 15, PH - Between 7.6 - 8.0, CL2 - 0. We use King British SafeGuard on one tank and TetraTec Aquasafe in the other ATM. Do you think that changing temperature could be causing issues? We do measure temp but I'm not certain how accurate our thermometer is. I just cannot find anyone else mentioning swim-bladder type problems that recur like this in multiple fish.

 

[the_lock_man]

Temperature changing will only be a problem if it's a large temperature change - the odd degree or 2 here and there will not be a problem.

Those stats you just posted up - can you run the same tests, incl GH and KH on dechlorinated tapwater, and post those up. If you've only got the problem at water changes, it points to something to do with the water being introduced. And no ammonia test result?

 

[jackaddict]

Oh sorry. Forgot that one. Ammonia is 0 (maybe edging ever so slightly toward 0.1) My pot of conditioned tap water came up as: GH - 16, KH 15 - 20, PH 7.6 - 8.0.

 

[jackaddict]

Any ideas?