Attempted my first GS foam background with Cork bark. Last night I trimmed up the foam and this morning the back wall was separating. I scrapped the whole thing. What are the most common reasons for this failure? I siliconed the the sides and back before I started foaming. I let that cure roughly 36 hours. Humidity has been high and it has been hot. I kept it in my garage for this whole process. Do I need to completely clean the tank to start over? will the silicone allover the sides and back be compromised by me pulling the foam off? If I need to clean it, please let me know how.