Cardinal Tetras and KH

fjf888

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Oct 29, 2007
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I read the prior thread about Cardinal Tetras dying. I am trying to establish a large school in my planted tank. What is the maximum recommended KH for them to thrive. My tap water has a fairly wide range of KH 3-6. Currently it is coming out of the tap 6 KH, I am concerned that may be too high.

I have also had trouble keeping them alive in quarantine, but that I believe was because my heater gave out and the temperature went to 69F. The remaining survivors contracted Ich. Previous posts seemed to reference that temp was critical. I throw hornwort in my quarantine tank as well, it seems to have the effect of increasing the PH to nearly 8 from about 7.5 because of all the CO2 is drained out, based on prior threads I believe that is not a factor. All other parameters are fine Ammonia, 0, NO2, 0, NO3, 10-15.

Any advice greatly appreciated
 

Tom Barr

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Jan 23, 2005
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I've never had an issue relating to KH and cardinals.
As long as you are good about acclimation and drip them, then they should be fine.
Several folks I know have the largest ones I've ever seen and they are 3-4 years old now and at a KH of 9.

The large groups in one client's are at 5.

Regards,
Tom Barr
 
R

Russ

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I have kept a group of 30 at Kh 5 for a year and they have done very well.

-Russ
 

Tom Barr

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Alan's KH is 8-9 and he's got the largest cardinals I've ever seen and the oldest.
The key was slow acclimatization.

Regards,
Tom Barr
 

VaughnH

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Jan 24, 2005
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Tom Barr;21564 said:
Alan's KH is 8-9 and he's got the largest cardinals I've ever seen and the oldest.
The key was slow acclimatization.

Regards,
Tom Barr
How slow is slow? An hour, a day, a week...? My guess is that no more than a couple of hours is very good.