Effect of High Alkalinity

[top_cat]

I have a 60L 'fish only' saltwater aquarium which I have been running for approximately 7 weeks.

I'm using Instant Ocean salt.

I introduced a clown fish on the 20/5/2007 after checking my Ammonia, Nitrite, and Nitrate were all ok. However the Clownfish died at the weekend, so I got another round of tests done at my local aquarium store and the Ammonia, Nitrite, and Nitrate were all still ok.

Could anyone suggest what the problem might be?

Test 1
Date: 13/5/2007
SG: 32 ppt
PH: 8.21
Ammonia: 0
Nitrite: 0
Nitrate: 10
Phosphate: 3
Alkalinity: 5.71+ meq/l (Test Kit Maximum is 5.71+)
Magnesium: 1250
Calcium: 400

Introduced fish (1 week later)
Date: 20/5/2007
Clownfish introduced


TEST 2 (Fish died, 3 weeks after introduction)
Date: 9/6/2007
SG: 30 (1.023)
PH: 8.26
Ammonia: 0
Nitrite: 0
Nitrate: LOW
Phosphate: 1
Alkalinity: 5.71 + (Test Kit Maximum is 5.71+)
Magnesium: 1440
Calcium: 420
(Clownfish died with the water at this level)

I used a test kit and tested the water twice for Carbonate Hardness. The first time the KH was 170 mg/L and the second time was 200 mg/L.

Is there anything from these test results which might explain why the clownfish died? The clownfish was tank bred and from a reputable dealer.

Thanks

 

[Snowboarda42]

Get a new test kit might be a good thing. Look for Salifert.

Also, how and how long did you acclimate this fish for?

 

[top_cat]

The main tests were done in the local marine Aquarium Store. I'm quite confident they are correct. The only one I personally conducted was the KH test which is Nutrafin brand.