Rock Wool on Potted Plants

> Subject: Newbie Question

> Someone on the Aquarium list recently mentioned that the rock wo
> plants are grown/sold should be removed before planting - said h
> remembered reading that it played hell with water chemistry some
> I've neither read nor heard this, so I come to you, the experts,
> elucidation.  :)

The rockwool is the growing medium when these plants are grown in 
an emersed state.  It is full of nitrate and phosphste, which is 
not a problem while they are emersed, since algae _can't_ grow on 
the leaves.  But if the phosphate and nitrate are let loose in a 
highly lit plant tank, they can cause severe algae problems.  

There is no good reason to leave the plants in the pots either.  
They will settle in quickly if your substrate is suitable.  The 
reason they are shipped with the pots on is simply to protect the 
roots in transit.

Karen Randall
Aquatic Gardeners Assoc.
Boston, MA