I used PEX tubing, brass corners and "T"s, stainless braid, stainless hose clamps, and 3/8ths vinyl tubing to make a MLT drain assembly. PEX is cross-linked Polyethylene, and it is rated to 200*F. I used the stiff white PEX in 3/8ths ID. You can get PEX in flexible rolls too, but they only sell big rolls at Home Depot. The flexible red PEX is what is usually used for radiant floor heating. A five foot length of the stiff white PEX was perfect for making the manifold for my Igloo Ice Cube.
There are four parallel sections connected at either end to a transverse section cut in several pieces. Two T's in the middle of the transverse lengths connect the inner pair of the four parallel sections, and corners at the end connect the outer two parallel sections. I drilled holes in the four parallel sections and encased them in stainless steel braid. I used SS hose clamps at every corner or T fitting to PEX junction to secure the tubing. Normally, PEX tubing is crimped to the brass connectors with copper compression bands, but the crimping tool cost $99, so I used SS hose clamps. A third T fitting on one of the end pieces connects the PEX manifold via vinyl line to a hose barb screwed into the inside of the 1/2 inch NPT bulkhead fitting.
Yeah, I know, a picture is worth a 1000 words, but the words were easier to post.
It works great. No clogs, drains as fast or as slow as you want, controlled by the ball valve on the cooler.
It was expensive and tedious to build. I don't really recommend it for those reasons, but it does work very well, and there's absolutely no way it's going to clog up. The PEX is very cheap. The brass corners (four of them) and T's (five of them) and stainless braid (from a washing machine hose) contributed almost half the cost, The 20 or so SS hose clamps cost $22, as I recall. They are like $10,95 per bag of 10. All in all, it cost me a rediculous amount of money at Home Depot pricing. I could have soldered up a manifold out of scrap copper tubing I have on hand for next to nothing, plus the cost of the T's and corners.