Substrate Conductive Cable Coil

---------- Forwarded message ----------
Date: Fri, 21 Feb 97 19:27:14 -0800
From: John <jlob at wpa_net>
To: Aquatic-Plants at actwin_com
Subject: Substrate Conductive Cable Coil 


Is anyone familar with these?  How effective do you think they would be?
Thank you for your comments.



*It also relies on a regular submersible heater for general tank heating 
purpose. But it has a coil to loop around that particular submersible 
heater and the remaining of the cable is hidden underneath the substrate. 
Heat, as produced by the heater, will conduct passively along this whole 
metal wire and create enough convection within the gravel. As you can 
already tell, its price is even lower than any other type as it doesn't 
require electricity to run!