Tank on its back and ready for jam session...


Apply silicone first (used to keep foam attached to glass and overflow longterm)
my son Zion helping....



Spread silicone around...


Start foaming...


Add a rock and foam around it...this one will act as a little ledge..be sure to distress the foam by moving it around with a stick and popping all the perfect little bubbles...distressing the foam as it rises three or four different times over the course of an hour will give you the most realistic look...


Example of foam NOT distressed...


Add sand and move foam around again with hands or a stick...make sure you have gloves on... you are trying to create a porous effect.