Problem keeping fish alive

[mteel7237]

I have a 75g setup and my 6 discus are doing great. The problem I'm having is that any other fish I add to the tank die within a few weeks. Oto cats, corys, cardinal tetras have all died shortly after arriving. I do weekly water changes and monitor water quality (ph = 6.8, temp = 85, normal water hardness, etc.).

I have a planted tank and the plants are thriving. I haven't notice the discus picking on the new arrivals.

Any ideas?

[Eddie]

How large are the discus? Are the discus now the only fish in the tank at all?

[Armandi_Fishcarer]

I'd like to ask if you are placing any nutrients in the water for the plants? What base, substrate/soil are you using?

Regards
Ahmed ;)

[Wahter]

Are you quarantining these non-discus fish before putting them into the main tank?



Walter

[mteel7237]

yes, I quarantine the new fish for two weeks before putting them in the tank.

I have 6 discus the largest is 5", the smallest 3". They are the only fish in the tank. (I did have a new discus arrival on 2" in size. After quarantine, he did well for several weeks then stopped eating and died within another 2 weeks.

I have a base of Seachem Flourite, cover with 1 1/2" of medium/small gravel. I do an every-other-day dose of Seachem Flourish Excel/Flourish Iron and Flourish Excel/Flourish Nitrogen. I also have a DYI Co2 setup.

[nesser]

Ive heard both Otto's and cardinal tetras have a hard time acclimatising to any suddin changes in water condition and it is worse if there stressed.Are you testing In all tanks for nitrite?Is this a newly cycled tank,Where you bought other fish was it the same source?If so what is there water like,I'm sure they could and should tell you.Cory's are to me a bit more hardy but I had one die solely due to the temperature of my Discus tank,not saying many fish cant withstand a high temp but some times it causes poor health due to stress.I suppose feeding could be a factor as well if there wasn't enough eatable greens.I'm not saying these are things you dont already know but it's the first things I would rule out.

[mteel7237]

the tank has been up and running for 1 year. I was thinking maybe the high temperature was the cause. I was just wondering if anyone else had run into this problem.

[Roxanne]

can you find out what temp they were kept in before you had them?..that may eliminate/confirm the temp theory...
Roxanne

[andy81]

are the parameters of the qt tank the same as the main tank. iask becuase i had a simliar situation andy once i made sure they were the same i had better results

[Roxanne]

good catch, my bad...forgot about the QT;)