AIO Clear tube mod

[f2bacon]

So a friend of mine really wants his Cooler Master ML240L to have clear tubes. He wants a custom loop but would never be able to maintain it.
I've seen plenty of videos on youtube of people having no issues doing it, but I just don't understand how that's possible. Almost all of them use food coloring (which I thought was a big no-no) and none of them do a follow-up to show how it's working further down the line.

The biggest comfort I had was that we'd be able to just re-use the liquid we already have, so no need to mess with different additives or ratios.
But it clicked in my mind that the easiest way to make sure there's no air is the finish the loop in a bucket of the liquid. But if there's only as much liquid as was originally in the cooler, wouldn't that be impossible? As it gets close to being full, there'd be little to no liquid left, definitely not enough to do underwater.
So I explained we'd have to dump the liquid, get distilled water, additives, and proper dye (if he wants to dye it) and he's still interested.

It was only a $50 cooler so it's not a big deal to him if we end up screwing up and having to go out and buy something else.
Another reason I'm interested is because if this ends up being a somewhat easy task, I would definitely do the same thing for my nzxt kraken x52.

Does anyone have experience with anything like this? I assume it's pretty straightforward in terms of get a clear tubing that's the same inner and outer dimensions, cut it to size as the old tubes, then finish the loop underwater and good to go.
Anyone wanna steer me in the right direction with some advice? Something more than the guys at microcenter reminding us that AIOs are made specifically not to be taken apart. I understand that there's anti-corrosive additives so that it never has to be serviced. The goal is to recreate AIO liquid so that we can change the tubes.

I strongly appreciate any help!

[GoldenLag]

21 minutes ago, f2bacon said:

He wants a custom loop but would never be able to maintain it.

the moment you open up an AIO its the same as custom loop. youve opened it up to the elements. just dont bother.

[f2bacon]

42 minutes ago, GoldenLag said:

the moment you open up an AIO its the same as custom loop. youve opened it up to the elements. just dont bother.

but what's in an AIO besides 1/4th coolant, 3/4 distilled water, and a little bit of biocide?
I understand I'm opening up a can of worms, and all the guys on youtube make it looks easy because they don't follow up.
But wouldn't it be fairly easy to just repeat their steps, using correct liquid?