Fish is dying in established tank

[SA]

Hi all,

I have set up a 45gl tank for about 2 months now, and cycled the tank with a
few cherry barbs, I then started adding a few of the following, mollies,
platys, guppies, neon tetras, pl*co, and a betta with couple of female
bettas.

Now in retrospect I realize that the above spices might have preferred
different water conditions but at the time it didn't occur to me. I have
zero nitrites & ammonia, very low nitrates, but the Ph is over 7.5 I keep
the tank at 78F and there's plenty of surface agitation from the water
return and lots of bubbles from airstone. I'm running a Fluval 304 with
activated carbon. Water is clear and no smell.

What puzzles me is that I have lost specimens from all of the above groups
at random times, and especially the bettas are having a very hard time I
replaced the male 3 times and they all died after being in the tank for 2
weeks or so. I cannot figure out what is killing my fish yet because out of
say 7 mollies 2 die but the rest are doing fine, the same goes for the
guppies, and the platys. The tetras had the worse survival rate, but now I'm
reading that they prefer low Ph can anyone comment on what I'm doing wrong?
As of today the last female betta died unexpectedly also. And I monitor the
tank, there's no fighting or chasing around going on... but first I see the
fish that gets quiet stays in one spot, then stars hiding, then gets to the
surface and spends time there, finally starts swimming while spasms set in.
Few hrs later the fish is dead.

I am a bit disappointed with my performance thus far and a bit at a loss of
what I am doing wrong. Hopefully I provided enough info here that maybe
someone can see a pattern or something I am doing wrong.

I really appreciate any feedback and thank you in advance.

Steve

[Dinky]

"SA" > wrote in message
...
> Hi all,
>
> I have set up a 45gl tank for about 2 months now, and cycled the tank with
a
> few cherry barbs, I then started adding a few of the following, mollies,
> platys, guppies, neon tetras, pl*co, and a betta with couple of female
> bettas.
>

Well, my first action would be to work on lowering that ph, 7.5 plus is
high, though many fish can adapt to it if the change is gradual, but going
from the LFS to your tank is likely more of a shock than some of them are
able to cope with.
Have you tested for ammonia, nitrites, or nitrates? All three of these
substances can kill fish, ammonia and nitrite at fairly low levels depending
on the fish. If ammonia or nitrite are present above a trace, then your tank
has not yet cycled.
What is your water change schedule?

[SA]

I used to do a 10-15% water change every two weeks, now I am thinking of
doing 25% once a month because I was reading that the tendency of the Ph is
to go lower with time, and my tap water tested over 7.5 when I did a test
straight out of the sink.

I have 0 ammonia and nitrite, I test frequently and have also one of those
ammonia alert thingy in the tank and it's been negative ever since the tank
cycled.

I also think it's the Ph, unless the fish stress each other out because they
are not compatible? But they really show no signs of aggression, even the
bettas male and three females got along fine, no fin nipping on the fancy
guppies or anything like that.

Thanks for responding!



"Dinky" > wrote in message
news:B6zwb.292902$HS4.2638663@attbi_s01...
>
> "SA" > wrote in message
> ...
> > Hi all,
> >
> > I have set up a 45gl tank for about 2 months now, and cycled the tank
with
> a
> > few cherry barbs, I then started adding a few of the following, mollies,
> > platys, guppies, neon tetras, pl*co, and a betta with couple of female
> > bettas.
> >
>
> Well, my first action would be to work on lowering that ph, 7.5 plus is
> high, though many fish can adapt to it if the change is gradual, but going
> from the LFS to your tank is likely more of a shock than some of them are
> able to cope with.
> Have you tested for ammonia, nitrites, or nitrates? All three of these
> substances can kill fish, ammonia and nitrite at fairly low levels
depending
> on the fish. If ammonia or nitrite are present above a trace, then your
tank
> has not yet cycled.
> What is your water change schedule?
>
>