[RML] Copper Toxicity

John Grylls (jgrylls at bendigo.net.au)
Fri, 16 Jan 1998 05:23:50 GMT

Hi Folks,

I am currently trying to grow aquatic plants in my tanks, using CO2
injection and PMDD fertilizer. Is anybody else doing the same?
I seem to be having some sucess, but I am concerned about the level of
copper that I am introducing with the trace element mix.

I am using Manutech trace element mix, according to the box this
contains 1.25% Cu, rather higher than I would have liked.

Assuming zero usage by the plants, at the rate that I am adding Cu,
with 25% weekly water changes I calculate that the long term
cumulative level will be 0.0133 ppm.
Is this excessive?

I must be very close to that level now, and the fish, freshwater
shrimp, snails,and plants all seem happy.
John Grylls