"Mermaid" schrieb im Newsbeitrag
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What is the limit amount of Nitrates for plants without harming fish? I
know
some fish want pristine waters.
Before I had cichlids and they could tolerate a higher amount of nitrates
but if it went too high, they would get scratchy.

Sorry for the newbie questions.

Thanks,
Paulette



Good question,

According to German standard literature, 200 - 300 mg/l are lethal for fish.
You should try to have less than 50 mg/l, preferably less than 30 mg/l in
your tank. You wrote "nitrates for plants", so you probably mean that higher
amounts of nitrates are good for plants. This might not be true. The same
literature states that excess nitrate concentrations will decelerate the
growth rate of both fish and plants.

Juergen