Alfredshouse is gone.....

[fkshiu]

Originally Posted by Jack

You keep saying Nitrate - which is not really toxic to fish.

If you say Nitrate (No3) being 0.8 - I think you mean Nitrite (No2) - which is very toxic.

Sorry about your loss.

It was just too many fish added at once.

Bummer.

Actually, nitrITE in marine aquaria is relatively NON-toxic to fish:
http://www.reefkeeping.com/issues/20...hf/index.php#5

What is concerning is the presence of nitrITE in the water at all which almost always means that ammonia (which is very toxic) was there previously. There should be zero nitrITE in a tank more than a year old unless there was a mini-cycle - possibly brought upon by the addition of so many fish at once.

I believe that the oxygen deprivation theory may be correct especially if the FX5 was the only form of circulation: Lots of fish are added to a tank with poor circulation. This causes the death of the weakest fish which in turn causes a mini-cycle which kills off the rest. When you finally do the testing the cycle is at the stage where's there's a little nitrITE left and rising nitrATES.

Your Alk reading is actually normal.