Here's an unlisted YouTube video of a run through of the levels.
I did know what to do and where to go but my first run wasn't too much slower.
The first level started badly as the virus didn't explode despite filling up.
The third feels quite slow as you move (as it is a big space).
I did find it hit and miss grabbing the virus. Some of the 'points' on the virus worked and some did not.
On the forth level, I liked the idea of filling up the two viruses but you can just pick them up and fill them! It's quicker. They need to be unreachable.
There is an issue with the yellow pipe on level five!
It was difficult to see the flow from the black pipe against the dark wall on level 6.
You can see roughly how long it takes and that there is a lot of time left on each level when they are completed.
It could still do with a confirmation message that you have done it before moving back to the menu.
The countdown clock could look better when it shows single digits.