ok i am thinking about venturing into building a new diy background for my 125 gallon aquarium i just bought but first i have some questions what is the best foam to use for the price first of all? what is the best thing to use to carve it? and also what should i use to coat it i dont really want to play with that whole coat in quickcrete then rinse like a hundred times? is there a safe paint i can pick up locally that wont leach any input would be great please.