I.L.
Don't beat yourself up on this. TV is not some evil thing. Footnote: in moderation, and depending on what you are watching.
At 16 months, there are more developmentally appropriately videos you can be showing him. Baby einsteins are great, and if he likes the ocean stuff, Baby Neptune is particularly good. The other good thing about these videos, and others like them, is that they are developed to be appropriate for the age of your child. Including the running time. These videos ared 20-30 minutes long.
Hope any of this helps.