Heck, I figured it had to be the comet water right off.

And what is this obsession some people seem to have with Tardigrades?

Oh, and if that acid stuff becomes inactive in oxygen, how come it isn't still eating away the ship outside in the vacuum of space?

Then of course, once they restart the "engines" everyone would be pushed against the "back" walls again, same as they would have before they were shut off in the previous episode...

And if they were supposedly going "near-lightspeed" before, they still would have been anyway, they wouldn't just stop and drift, or even slow down, when the "engines" were off...

Plus how were they supposed to be "near-lightspeed" with what amount to fancy rockets, anyway? The only possible way that could work is if they carried an enormous amount of "fuel"/reaction mass, which would probably require doubling or tripling the size of the ship...

Not to mention the time-dilation effects...