Help with sealant.

[Tracy33]

Hi all , so i have ordered the new viv today ,and is on its way !! . So can anyone tell me what is the best sealant i should use for the job . The last stuff i used dried like rubber , and i`am sure this also made the tank smell , when it came into contact with the snakes poo and what else ! The new viv stands at 3ft H x 2ft D x 4ft L , i will send some pics , when it is ready . Tracy.