I would consider Tygon Silver Antimicrobial instead of 2075.
http://www.petrastechshop.com/1id3odtysian.html
There is no need for that heavy chemical resistance 2075 provide, but antimicrobial tubing may let get away with pure distilled water and this is a good thing, as i personally hate to mix any of that additive stuff into my loop,
poisoning and contaminating it.
Tygon Silver is also plasticizer-free and has low water absorption rate , the main two factors which,presumably, affect tube staining over time.