Help, something's growing in my 1-day-old watercooling setup!

[WeaselBlade]

Filled the system yesterday afternoon, not even 24 hours ago. Coolant is a mix of steam-distilled water and Zerex racing coolant. Not sure what the ratio is, but between two systems I've used about 2-2.5 litres of water and about 11 oz of zerex. Water is a nice(gag) pink color. According to cooltechnica, 11oz of zerex is enough to treat over 6 litres of water, so I should have plenty...

In the T-line at the top of the system, there are two little clouds, look just like the sort of stuff you get if you leave juice too long.

There was a small amount of brownish scum on the inside of the tubing used for the t-line; i ran out of new clearflex and had to use some I'd been using for testing. I scrubbed it off as well as i could reach with a pen, and couldn't see any more when I put it in the system. Neither ammonia or CLR seemed to have any affect on it.

How is this happening?? The system is 25 ft away from the only window in the room, and never receives direct sunlight, while indirect is pretty limited, as the window hardly gets any sun itself. I was under the impression that zerex was nasty enough to prevent things from growing like this, seems I was wrong...

What should I do about it? Drain the T-line to get the lumps out is obvious, but do I need to drain the whole system? Hope not, I've got no more zerex and I have to order it online... Can I add something to the system to prevent this from happening again?

[tong]

zerex blows. leaves residue everywhere. Go to an audi or vw dealer and ask for blue/red/pink/or pourple pentosin antifreeze it's very nicely priceed and from the few silent users taht use it it ROCKS. Got some now just waiting on a few other items to finish my water cooling setup

[maxSaleen]

Must be a fungus of some sort. Zerex does blow. Do you actually have "clumps" in your system or just in the T-Line?

[redleader]

Its almost certainly just solute from the Zerex. My guess is maybe you put too much in and not all of it dissolved fully. It could also be some residue from the metals used in your system and its solder. I doubt its actually alive though. Your coolant should be plenty toxic and has no nutrients.

[maxSaleen]

I was thinking that since "clumps" lends one to think "gunk" it is possible that it is the result of some strange chemical reaction between the zerex and something in your system.Brownish scum might be an indication of some sort of corrosion, though its location in the loop makes this unlikely.

WeaselBlade: More details on your system would help us help you.

[gazorp]

Originally Posted by maxSaleen

I was thinking that since "clumps" lends one to think "gunk" it is possible that it is the result of some strange chemical reaction between the zerex and something in your system.Brownish scum might be an indication of some sort of corrosion, though its location in the loop makes this unlikely.

WeaselBlade: More details on your system would help us help you.

and pictures!

[WeaselBlade]

First off, more system details: two heatercores(brass, I'm pretty sure. Larger than a single 120mm fan, not long enough for two. Using a pair of 150mm/12v fans @ 5v on them.), one mag5, two mcw6002-pxs. Assorted fittings, all brass or plastic. Clearflex 1/2" ID tubing and generic clear 5/8" ID tubing from a hardware store. This is cooling dual 1.6lv xeons at 3.0/1.55v on a PC-DL, CPU temps as given by speedfan are around 37C give or take a couple degrees depending on time of day, under full load from four instances of Folding@Home. I don't have any info on water temps beyond that, but clearly they're fairly low.

AFAIK the heatercores were new; bought them off a guy in the FS/T section of this forum, but they looked unused, and I shook some solder-balls out of one. Both were flushed with tap water followed by distilled water before use. Aside from the solder, no gunk/old coolant/anything at all came out, and the fins were all in mint condition. The waterblocks were brand new, the pump was used, but I took it apart before using it, and the insides were clean.

Pics are a no-go right now, I don't have a camera of any sort.

I shut the system off and looked through all the tubing for more of this stuff; the tubing seems somewhat cloudy in places, but using a bright light aimed right at it, I couldn't find any more such lumps, even after leaving it for at least an hour there were no deposits/lumps anywhere else in the system. I then drained off the coolant in the T-line into a jar. Looking at the bled coolant, the lumps seem to have disintegrated into little bits, mostly white. Refilling the T-line with distilled water, before it gets a chance to mix with the zerex/water mixture I can see little bits of whiteish stuff floating around in it.

I'm puzzled... At this point I'm leaning towards the solute theory, given the appearance of the clumps once drained from the system. What I can't figure out is why it would appear in the T-line; neither the bits or the clumps are/were floating to the surface, they settle to the bottom, or near it. The T-line comes off a plastic barb screwed into a brass t-fitting at the top of the case just before the pump inlet-it's capped with a bass cap, but the water doesn't reach that far.

Possibly the same substance in the rest of the system accounts for the slight cloudyness in the tubing, but if that was the case I was expecting to see it settle after the system was off for over an hour... I'll take a look at the drained coolant again tomorrow to see what it looks like then, maybe it will provide further insight.


So, if redleader is right and I can blame this on the Zerex, that leads directly to a couple more questions:

How bad is such 'solute'? Is it going to damage my pump/hurt my temps by coating the insides of my waterblocks/clog my heatercores? Or is it mostly just going to look ugly? Should I try and partially drain the system and refill with just water, to get the concentration down?

Secondly, what should I replace it with, if it needs to go? I went out of my way to find Zerex because I had seen it compared favorably to Water Wetter... First I have heard of this solute/residue problem. Can anyone tell me more about this 'pentosin'? What's the difference between it and normal antifreeze?

Thanks for the help all who replied.

[bobkoure]

Originally Posted by tong

zerex blows. leaves residue everywhere.

Your actual experience with ZRC? Or repeating what you've read elsewhere?
If it is your own experience, what percentage were you using? Other details?
FWIW, I've used it at 10% solution (spec'ed by Valvoline at this concentration for automotive applications) in a number of systems and have not seen this - but maybe I was just not looking in the right place.

WeaselBlade is using it at something like a 13% or 16% solution (allowing for both US and UK ounces) which doesn't sound way off what I've been using. Cooltechnica recommends 5% (thermochill too, I think) or about a third of what's being used here. Maybe there's an issue with over 10%? I would guess, though, that it's something else. Are the particles hard or waxy? What happens when you run straight distilled water? Speaking of which, where did you get the distilled water?

As a side issue, yes ZRC is pink. Automotive coolant additives tend to be color coded so a tech can be sure to top up with something compatible (or a race tech inspector can be sure you aren't running anything with glycol which is banned on many(all?) tracks as if it spills it's horribly slippery and must be thoroughly washed off - fuller's earth won't cut it)