dr. dave wrote:
>{snip- discussion on polycyclic aromatics etc.and how activated charcol
>is made and works}
>In practical terms what this means is that carbon filters should not be
>used in a plant tank which receives regular additions of micronutrients
>(if you want to maximize the effectiveness of your micronutrients).
>I have recently removed my carbon filter and have noticed an increase in
>plant growth, though this anecdotal evidence is hardly conclusive. One
>concern is that the load of organic compounds (such as urea etc) in the
>tank could increase to toxic levels, though with lots of plants and few
>fish in the typical plant tank this may not be a problem ... something to
>think about.
>Dr. dave.
When I first set up my planted aquarium, I used an activated carbon filter
(I missed the warning in _The Optimum Aquarium_.) For the first two
weeks, I was never able to get a measurable amount of iron 24 hours after
adding an iron fertilizer. This included times when I added 2X-4X the
recommended dosage. Upon the advice of the fertilizer manufacturer, I
removed the carbon filter and was immediately able to maintain ~0.1ppm Fe
using near the recommended dosage. Plant growth improved also.
This occurred about two years ago, and I have not noticed any ill effects
without the carbon. I am using PURIGEN by Seachem (They claim it is a
substitute for carbon that does not remove trace elements) as a carbon
substitute. My experience with it supports their claim that it does not
remove chelated iron, but I do not know if it is in any way beneficial
other than its placebo effect on me. The plants and weekly 25% water
changes, coupled with a fairly light fish load may do as much to keep down
the level of harmful substances rather than the PURIGEN.
Doug Skokna in warm, cloudy, with a smidge of rain Houston, TX.
First round: Rockets 3 - Lakers 1. :-)
Second Round: Rockets 0 - Supersonics 2 :-(
Next game: Friday