Spose my thought was that say a 4 foot section of the black extrusion would be significantly more material than say the CPU water blocks used by OP. Heat would be distributed throughout the large run of thick aluminum before a ton of heat went to the air, and both passages with water flowing through them would be able to reduce temps of the extrusion for purpose of keeping cobs safe and tent temps bareble. That’d be 8 feet of 1/4” water flow utilizing both holes. My gripe or lack of understanding with those using square tube: is your entire tube getting filled with water? I’m imagining that happening if your outlet is the same size as the inlet.. and the volume of water in a 1” square tube is a little less comfortable than nice passages with threaded fittings even if not as effective at moving heat out of the tentProblem with that kind of profile is there is much less surface area in contact with your water. Plain square tubing maximizes that. The EZtube you showed above would work much better.
I can’t find anything conclusive on max flow rate of a 1/4 inch passage but it seems like 30gph. With two supply lines at the inlet side (instead of a tee) I could supply 60gph through the rig.
Not sure why I’m blabbing here, I already have nearly 2500 actual watts of passive and active cooled leds and a spare 4 cob / 200w setup to evaluate effectiveness on.
Thought being: some people, self included, just want to find a cheaper alternative to pin heatsinks and not bother with wiring up cpu coolers. A $20 3-4 foot extrusion to host 4 cobs for a 4 foot wide tent sounds pretty nice and the extras don’t tack on that much either (barbs, teflon tape, a tap kit [or 8020 inc can pre tap the holes], a pump, and some tubing. Maybe $35 all in and cheaper for additional lights. I paid over $100 for 4 heavy pin heatsinks with shipping...
And easy as hell to hang with the T-slot, which would also make a convenient place to tuck wires. Could drill straight thru the T slot and not hit either water passage for passing wires down to cobs, and also screw cobs in diamond fashion or whatever to miss water passage.
Will follow up in a few weeks, lead time sucks for that particular extrusion