what material for my resevoir?

ok so i desided that i am going to build my first wc system and i was wondering what material i should make my res out of. Should i make it out of metal or plastic? Cause i was thinking that if i made it out of a copper pipe it might cool the water in my res faster than if it was in a plastic res. Any input would be nice

well copper would make it cooler but it most likely wont be worth the time and effort to make it, id say a ~1c drop. i wouldnt even get a res but if you must then make it out of copper with a fan blowing on it. then post results

well if i have time i will do both but the one thing that makes me want to stay away from the copper is that i wont be able to see any cool uv reactive water. Thx for the fast respond that was like 5 mins.

I would use acrylic (there are many varieties, look em up)
Check out Thorilan's rig for a picture of an AWESOME acrylic res that's homebuilt.

And yes, use stuff to leak-proof it.

I built mine out of pvc pipe and put 2 1/4 right angle hose barbs in it besides my 1/2 id barbs. I then put a short piece of clear tubing so you can see the water level. I searched and searched for something to make a reservoir out of that was clear and never did find anything I really liked.

Tap plastics sells round tubes of acrylic with 1/8" thick walls. They ship as two 3 foot sections, so you should have more than enough. The best thing is that you can also get various normal and UV reactive colors as well the standard clear type. I just got my drillbit for 1/2" pipe thread, so I'll be building my dual 2" tube res fairly soon, just after I get my gpu waterblock (it's been "in the mail" for a WEEK now!) to provide measurements.