Well, the red tubing is actually cheaper than EKWB's own clear tubing by about £5, so that's why I'm going with red over clear tubing. Normally, the red tubing is like £30, but they have a "limited stock" price of £9.60. All these should be euros, not pounds but they're practically 1:1 these days. Plus, I don't want to go with just distilled water because the red fluid in the reservoir is the main part of my theme. But yes, I do agree that red tubing would otherwise be a waste of money, I'm just ordering everything from EKWB and their clear tubing is more expensive than the red tubing they're selling, for the exact same length.