personally, I would not recommend adding anything to the water, just use the DW alone. use the metheod that kirock suggested to flush/decontaminate your water, that's some darn good advice

as far as the bacterial growth is concerned, it can be minimized, but not completely avoided. that is why you should flush the system every 6 months to 1 year IMO. you also need to clean the pump when you flush it as well if you want it to last.

also Kirock, am I to assume you mean de-ionized water when you say DI? I have always heard that DW and DI have pretty much the same conductivity levels? is this not true? I am curious as to what would make DI better than DW? and also, where can you buy DI water, I have never actually seen it in a store?? (you'll have to excuse my water-ignorance )

You can't get 0 algae in the water, it'll grow sooner or later. Cleaning out the system would be recommended once in a while.

I probably will throw in anti-algae crap into my system.

This is why buying good parts are important. Getting parts that will work with contaminated water would make things easier for you, since you don't have to make sure your water is always clean.

Everyone is concerned about keeping water uncontaminated. Does anyone know why contaminated water is considered bad? Its not. Being conductive is bad. And its not because it gets over all your components and blow it up, because its not supposed to get onto your components. And even if it did, there's strong evidence that drying it out completely (leaving it out unused for 2 weeks) will fix it (depends on what it gets on). The main reason you don't want the water to be conductive is so that your parts do not rust. Chemistry 101: 2 different metals in electrical contact will degrade one really really fast. This causes blockages which is bad.

Now that thats out of the way, lets look at how we can tackle the real problem: the blockage.

1: making sure its not in electrical contact. This means you keep non-electrically-conductive water in the system.

2: Use everything from 1 metal. This is not very viable, since you've got screws and crap made out of steel/iron/etc. But what you can do is to make sure every component thats in contact with water is made of copper (or whatever your waterblocks are made of). Do research on the pump you want to use. Pumps which have only plastic on contact with water will be great, since chances are they won't be using copper in there.

3: reduce the chance of getting something stuck in the waterblock in the first place. This means staying away from waterblocks which have mazes and squeeze water through small openings. Easier said than done, since getting huge surface areas and getting good heat transfer depends on turbulence and water getting into contact with surfaces.

Since you can't do anything about that without compromising your temps, the other solution is a waterblock that can easily be dissassembled and any clogs removed. Stay away from acrylic tops tho, they tend to crack, sending water into your system.


I hope this helps in the "lets keep the water pure" discussion.

Yes that's what I mean, DI is de-ionized water, it's an industry jargon. DW (distilled water) is a much lower quality semi-DI water. DW is water that is filtered, then boiled to steam. The steam is collected and condensed back into water, just like the process of making liquor(Liquor/alcohol manufactures have the trade name of "Distillery"). The resulting water is much better in terms of ions and particulates but the process is not perfect. Alot of the ions simply evaporate with the water and of course recondense with it and therefore are still present in the finally product. The resultant conductivity is in the range of 500-700K ohms/cm.

DI water can be much higher then this (in resistivity, which is what we want).
My first experience with DI water system was in a Dialysis ward in a hospital.
I was a Dialysis Tech and we maintained all the equipment etc. That system was capable of running 20 dialysis machines simultaneously with each machine having a flow rate of 2-3L/min. The conductivity was in the range of 1-2Megaohms/cm. In the semi-conductor lab I spoke of in my previous post, the system was much smaller but capable of 18-20Mohms/cm. If the conductivity fell below 10Mohms/cm it was time to change the cartridges.

Resistance per centimeter is the standard for measuring DI water pureness.
It's literally a high impendance meter with the probes physically seperated by exactly one centimeter.

CMH:

I thought that IS what we are talking about, contamination(of whatever kind: minerals, ions, bacteria)=conductivity, which is bad. You make excellent points here about the water cooling and have the experience. It's you and KingC that are really helping jezreex, I'm just adding a little knowledge to the mix in a limited capacity.
What I was recommending is called "Pacification" and is used in chem and physics labs the world over. The process is to use the substance you WANT to system/container/object to be filled with to "clean" the system of other unwanted substances. Heating the system during the process increases the effect. Also applying negative pressure (vacuum) encourages degasing (micro pockets of air). This is based on the basic principle of particles moving from an area of high concentration to an area of low concentration.

I'm not sure about the rusting point you made CMH. I would hope the system is made from copper pipe, plastic parts and either aluminum or copper cooling block, thus rusting is negligeable. I though the real point here about water quality (DI and DW) was more of a safety/insurance thing just in case the system sprung a leak!

Finally, I'm not sure where you could buy DI water, you might be able to get some from a local hospital. Their labs would have many DI system in them. If you had a contact or just asked real real nicely they might give you a bucket.
If they do, make sure you pacifie the container with at least DW first.

Cheers.

great info kirock. I learned alot today It would seem that DI is best, but is not available to most of us. so distilled is still the way to go (as far as water is concerned).

One important thing to note is that products are marketed to make it seem like you set up a water cooling system, fill it up, and forget about it. this simply isn't the case. all cooling systems require maintenance at certain intervals to keep them working efficiently. air coolers require the least amount by just removing the dust accumulation. water cooliong systems require a bit more (removing dust from radiator, flushing all water passages, pump cleaning). you cannot just set up your water cooler and forget about it, if you do then you will find that it either stops working as efficiently or just stops working all togther.

In my opinion it is not worth buying expensive cooling liquids either, because you will still have to flush it out like a water filled system and you'll just be wasting your money. a gallon of distilled water ususally costs about $1, where a small 500mL bottle of PC cooling liquid costs about $30, you do the math.

algea and bacteria will grow over time, while this will not damage anything, it will reduce the overall effectiveness of the system by reducing the flow. this is why you should flush the system and clean the pump's impeller and rotor

Don't worry I didn't. LOL

How often does a well built watercooling system spring a leak anyway? I'm talking something that's been leak tested, built with quality parts, and regularly maintained (checking for wear and stuff).

if you take your time and build it correctly... it should never spring a leak.

i have had leaks in the past due to hasty setups, but that was my fault by being careless and rushing through it. I have never had a leak after i took my time.

And therefore, I really think the need for 20mOhm water is not justified (exaggeration there). Just make sure the algae problem is resolved, don't worry about how the anti-algae solution will make the water conductive, cos you've got more important stuff to worry about, and that problem can easily be handled.

Oh yeah, about the rusts and all, its kinda true that these metals don't flake off, but to some extent, it still does ionize, and these bits still get oxidized and precipitate out. You'll notice its effects after a few months or years. Small problem, but I think most people would want to keep their comps running for a few more years. You can add a filter to overcome this problem, but I think its not worth the trouble. You'll have to get a bigger pump for that.

Are all u guys nuts about Chem? I bet my A-Level Chem teacher would love u

I love Chem, everything just falls into place

a water cooling rig should not leak, but you really don't plan for it to either

that is why it is a good idea to help protect your components by using a non conductive fluid to cool your rig, you never know what might happen. i had leaks that just appeared over time, they didn't do any damage because I had used distillled H20 instead of tap H20.

i would not recommend using tap water, and i would recommend flushing it out as best you can before lnstalling it.

I agree with most of what you say, but...

where? from what component(s)? and why?

leaks should not just "happen" over time.

Also many of people and including me, have had problems with the CPU block cracking because it was made out of plastic. If you are going to use one do not over tighten it. It will cause leaks.

I really really suggest you NEVER to consider those acrylic top CPU blocks. They look pretty till they yellow out/crack. Then they are just a pain.

Secondly, no matter what water you use, you will not get it unconductive for long. Especially since copper kinda ionizes (one reason why you don't drink from hot water taps) readily in water. So if you're saying you had deionized water in your system for 2 months, I can bet if you tested the water for conductivity, chances are its more conductive than tap water. And it just proves again that water on comp doesn't permanently fry it.

When I had a Game Boy color back in the day (1998 or so) I put it through hell and it still worked. maybewent in in the washer three times, and after letting it sit in the window seal to dry after a few days I was back to playing it (I could beat blue version in 2 hours with a my guys at level 100). So back to the main point in my experience water and electronics usually don't have permanent effects.

Good, so the lesson here is: don't be too worried about what kind of water you put in the system: it makes little difference.

Personally I'd put the purest water I can get, but its only because I don't want unwanted metal ions in there. I wanna keep my whole system Mg, Pb, Fe, Na, K, etc, etc free. Oh yeah, and I'll probably add CuSO4 to the mix, to give it that nice blue colour and to prevent algae from growing. It'll be super conductive, but I'm gonna leak test before installing, so there

everybody thank you for all your help I have learned a lot from this thread alone. last sunday I was able to buy a distilled water from walmart as you all suggested it can be bought in supermakets but I haven't drain the system yet. I know I have to flush and drain the system and I undrstand what you all are saying but my problem is how to flush with my particular system. I will give you a picture of it and maybe you can help me in detail how to do it with my system. I am using the corsair coolwater. the reservoir doesn't have a drain hole only a fill hole and it fits on a 5 1/4 drive bay so I placed it at the top of the bay as suggested by corsair. I think there are two ways for me to drain the system (one) pull-off one of the tubes and get rid of the water in it and return the tube back but it is virtually impossble for me to pull out the tube from the reservoir because my case is now very cramp and I tried to pull it off and it is really hard to pull off and if I will really try harder it call be pulled but the danger is the water I believe my computer parts will be bathing in water if that is the case. the only recourse for me is to pull it off from the pump but again the tube is really tight. (two) another way is two something that will suck the water from the reservoir but my problem is the remaining water inside the tube how will I do take it off. my idea is after sucking out the water from the reservoir I will fill it up with DW and run the system. after a few minutes I will suck the water from the reservoir again and run the system again until all the old water is out. is this a good Idea though or is there a better way to do this? I need your input. thanks a lot in advance.

i dont know what your specific system is, but it sounds simlialr to mine. i have a 5.25" bay reservoir with an inline pump at the floor of the case. to drain mine i simply move the pump slightly out of the case and disconnect the inlet house (from the resi) and let the water drain into a bucket. then i carefully remove the resi and drain the rest.