Re: aquatic plant alleopathy

[Thomas Barr <tcbiii at earthlink_net>]

> The problem with determining whether or not alleopathy is happening in a tank
> of mixed species is that one has to work out a method of having a control
> tank, e.g. one that has all the same species, but which doesn't allow the
> allelochemicals to accumulate. I wonder if ultraviolet sterilization would
> also destroy allelochemicals---at least those in the water column. Does
> anybody know anything about this?
> 
> --
> Paul Krombholz in steamy central Mississippi

I have to agree with Dr. Ole Pederson. I know 2 of the editors for Aquatic
Botany, a bunch of aquatic weeds folks, all will say the same thing. It's a
mild effect at best.

Activated carbon will remove alleopathic chemicals.
This can be placed in the substrate on one half of the tank etc.
Everything would be the same except for the carbon in the substrate.
he carbon might bind to potential nutrients that may effect growth so you'd
need account and test for that also, but this is not likely to cause a
significant difference IMO based on terrestrial systems that have been
tested.   

Regards, 
Tom Barr