Jody, Are you talking about Profile line soil substrate? If so, you can find out a lot about them by searching the archive on Aquatic Plant Digest. Search the archive on Profile and Turface at http://fins.actwin.com/aquatic-plants/index.php If I recall correctly, Profile's aquatic gardening soil raises the pH and carbonate hardness of the water a bit. It also adds phosphate to the water which can increase the chance of an algae outbreak (someone in Tennessee Aquarium shared some data on this with me at their studio/plant holding area.) Tomoko ------------------------------------------------------------------------- This is the apistogramma mailing list, apisto@listbox.com. For instructions on how to subscribe or unsubscribe or get help, email apisto-request@listbox.com. apisto-digest@listbox.com also available. Web archives at http://lists.thekrib.com/apisto Trading at http://blox.dropship.org/mailman/listinfo/apisto_trader