McPixel 3

Swim up to the wall above or below before entering the flow - makes it a little easier. Still needed 30secs at least of tapping.

Yeah it helps if you go right against the wall above òr the below the first pipe on the right in starting room and keep pressing A as fast as possible whe holding right and it should take 15‐20 seconds if vigorously tapping A

Thanks Ive xd

It's actually way easier. On mouse just click it once and wait, on controller just hold right. Button mashing does nothing for both input methods. On controller you can also swim below/above the pipe first to make things quicker.

Yes, like last dude said, you just hold right on dpad or analogue stick, there's no button-bashing. You swim above the flow till you reach the wall, then swim down and just hold right ➡️, facing the outlet hole. You'll slowly swim into the hole and get the achi on the other side, when the countdown just passes 2:00 (takes just over 30s).
It's 4C8, the blue dot icon 🔵, so it takes awhile to skip past the 7 previous stages.

Yeah I'm reading this thinking, why people smashing buttons, when all you need to do is hold Right on d pad. Done...