I came across a old tank that is 36x18x18 with a slate bottom. Very old tank not sure from when, but the slate is cracked and it doesnt hold water. But the glass is 1/2 thick, and im thinking for my diy 405 i may do a split veiwing window or maybe just make another tank with a dual veiwing window. Is there anything different i should do if i make another with a dual window that you wouldnt do with a single veiwing window. Cause i have all kinds of ideas for the glass since it was free