GL with your window reseal VL, I really hope it works out for you this time.
I am considering using large sheets of water proof cement board attached to plywood and then selaed with pond armor.
This I hope should help create a strong leak proof tank.
I was thinking of 15-20mm ply and 6-9mm cement broad.
http://www.ibs.com.au/gyprock-fibre...x44rqtqsCFWdMpgodLhF6fQ#FIBRE CEMENT SHEETING
I am considering using large sheets of water proof cement board attached to plywood and then selaed with pond armor.
This I hope should help create a strong leak proof tank.
I was thinking of 15-20mm ply and 6-9mm cement broad.
http://www.ibs.com.au/gyprock-fibre...x44rqtqsCFWdMpgodLhF6fQ#FIBRE CEMENT SHEETING