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Didn’t mean to put anime, could possibly be a British’s tv/vhs show
The crocodile behind a shower curtain thing reminds me of the mobile phone game Where's My Water, which has an animation like that after each level is completed. Too recent, but I might as well mention it
Some guesses:
Lyle, Lyle Crocodile: The Musical - The House on East 88th Street had a crocodile in a bathtub according to the IMDB description but only a tiny segment is on youtube so I have no idea what happens in it.
Also here's another crocodile cartoon, Christopher Crocodile, it has a flood and a bathtub being used as a boat in this episode, towards the end: https://www.youtube.com/watch?v=36ck1w72h60
Spot the Dog was another British cartoon from around that time with a crocodile character.
Edit: another suggestion, Round the Bend , I don’t know if there’s a shower in it or not though https://youtube.com/watch?v=B7G6cVSP5QY
This isn't completely matching the description but I thought of 'All dogs go to heaven', this is the crocodile scene: https://www.youtube.com/watch?v=27U6dyYE9rA
Lyle, Lyle Crocodile: The Musical - The House on East 88th Street from HBO Musicals?
I’m trying to remember a tv/vhs show I watched at a young age, I’m 22 now so I watched it around the age of 5 (2000) late 90s, I just remember a creature (possibly a crocodile) taking a shower and seeing his shadow behind the shower curtain, then a flood occurs and use the bathtub as a boat. Any ideas ?