Tubing size doesn't matter, you wont notice a temperature difference.
It is generally best to go with the thicker walled tubing however, this just helps to reduce kinking and thinner walled tubing is fine when installed properly (with common sense)
I would go for either 3/8" ID 5/8" OD tubing, ot 1/2" ID 3/4" OD.
Get fitting to match the tubing, you can get 3/8" tubing on 1/2" barbs, but it's a total pain and really not worth it.
If you want the easiest and bet looking solution, you could get compression fittings, but the cheapest will be barbs and cable ties.
Originally Posted by bfeng91
I don't agree with the overkill part of zipties/clips for 1/2-3/8. I wouldn't risk leaving my tubes unclamped in my computer.
Honestly, if you manage to get 3/8" tubing on a 1/2" barb, the problem is getting it off again...
I recently tried it out and I had to cut the tubing off the barbs! It's pretty safe imo. Edited by Crabid - 5/11/11 at 5:02am