
A coworker of mine gave me a great idea: to buy lava rocks and break and rebuild them with aquarium silicone the way i want them. My only question is, would lava rocks from places like hardware stores be safe? Not the BBQ ones, more like the landscaping ones. They sell a lot more of them at a much lower price than pet stores offer them, so if it's safe (or i can make it safe) id rather go with that option.