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Re: Losing corydoras :-(

Subject: Re: Losing corydoras :-(
by Fishlady on 2018/10/20 15:40:05

There's nothing obvious from what you've said, except that 0 nitrate rings alarm bells. As the final product of the cycle, it's almost impossible to have 0 nitrates in a stocked tank. That may indicate that the cycle failed recently and produced ammonia and/or nitrite spike which killed the fish.