Thinking about going full custom loop, "worth it", risks, etc

So, yeah. I'm thinking about finally going for a full custom loop, it would be my very first foray into water cooling and as such I have quite a few questions for the veterans. The pictures included are my case with a small diagram of my planned loop + my shopping cart so far. I've already done the bulk of the research and asked around, so as far as I know this should be everything I need (I already have a whole bunch of excellent static pressure fans for the rads). If I'm missing something, if I don't have enough tubing or if the pump is somehow too weak for what I'm planning then please point that out, those are some of the things I'm worried about right now.

Fan setup: would my diagram be alright when it comes to airflow? I could also get rid of the bottom fan and go for push/pull on the 240 rad instead, I just want to make sure that I have positive air pressure in the case and that everything works out fine. Also keep in mind that only the fans on the rads are 120mm, the remaining fans will be 140mm ones that are controlled independently.

Rads: From what I've read those rads are excellent and I suppose 360 + 240 should be enough for 2 GPUs and a CPU when they're that thick. I've checked compatibility and they'll fit just fine in my case.

Pump/res combo: I've heard that those 5.25'' bay units can be a bit noisy, but it seems like such a nice solution. How hard would it be to fill that thing, I assume you'd connect all the tubing and then lean it out of the 5.25'' bay to fill it, do all the filling and bleeding and once that is done close it up and push it back in the 5.25'' bay? How hard would draining be with my setup in general or with that res in particular?

Fittings: First of all, wow they're expensive. I'm pretty sure I have enough (2 for each component). My question would be, should I go for quick disconnect? It would be even more expensive and they add more resistance from what I've heard. The 4 90° adapters are also in my diagram, the blue circles.

General questions: "is it worth it" is a silly question, I know. But I'd just like to know whether you'd do it for my current system, with 2 R9 290s, when I'm probably upgrading in a year or two anyway. I could also wait for HBM 2 cards and possibly Zen and just do the whole project when I swap all the components anyway.
The risk, how likely am I to screw up on my first attempt? How likely is it for a leak to appear during use? How likely is it for the pump to die without noticing it, etc.
Am I overspending on certain things? Buying it all from one source is convenient, but EK might have inflated prices on some components, I don't know.
Is it really the best solution to just buy reference cards and then OC them once they are under water? Isn't the power delivery a limiting factor on the reference designs?
How many parts can I re-use across multiple builds/years? I assume everything except for the GPU blocks, right? The water-block is universal and fits virtually every modern socket (and hopefully future ones as well), the rads and tubing and whatnot should also work just fine in several years, maybe you'd have to swap the O-rings on the fittings. The GPU blocks are what's going to be changed every GPU swap, but I hope that they'll sell well with the used GPUs.

I guess that's about it, thanks to everyone who takes the time to read and/or answer this.

First off good design champ - a 240 and 360 is more than adequate for cpu + 2 gpu's.

  • if anything change the front radiator that has its ports on the top. eg
  • worth it? imho - custom loops are worth it provided they satisfy a) quietness b) good temps. the bonus being aesthetics
  • 5.25 bay units are only ever noisy if they vibrate in the bay - small micro dots of dampening material (rubber for example) in certain spots (eg screw points) remove these noises though (source: I've got a d5 bay res combo myself)
  • fittings are expensive, no way around that unless you can get some good 2nd hand gear (just check the rubber seals). Also shop around - depending on where you are in the world there are some great retailers about: frozencpu, overclockers etc.
  • re-using wc gear pretty much goes with the territory, I've got a rx360 rad that I got when they first came out and its been in a few builds now, just keep the gear clean (flushed) and then just clean em again before use - helps if water and not pre-mixed coolant is used as well as some leave gunk.

It's nice to hear that the overall design isn't completely flawed from the get-go.

What exactly is the benefit of having the ports at the top like that? From what I can tel I just need a 90° adapter for the outtake there and it should work just fine.

It's mostly about noise and cooling, possibly higher overclocks. I'm just not sure whether it's worth to do it right now or whether I should wait a year or two until I actually upgrade most of my system anyway.

The D5 bay res combo comes with dampening material from what I could tell, so that would be fine? How hard is it to fill those things, am I right in that you have to pull them out for the initial filling?

I wouldn't feel comfortable buying fittings second hand honestly, if 6 bucks for a compression fitting isn't outrageous then so be it.

Okay, that's nice to hear. The coolant I'll be buying is just distilled water with pre-added anti-biotic and anti-corrossive. edit: nvm, so just distilled water + anti-corrosives and anti-biotic? 2nd edit: this should do the trick I suppose: 1:50 anti-corrosive + distilled water. No other junk that could gunk up my system, and distilled water is so cheap that I can just use it to flush everything out before assembling it.

*Hi, I would add a drain port, its a must, belive me :D also I had bitfenix bay res, its not difficult to fill , use large syringe 160ml and a piece of tube, it takes a while.It does vibrate and its not a good idea to have HDDs below as some have vibration tolerance limits.Also if you plan to use colored coolant it can be difficult to clean the res as they tend to stain, mine did ;( You shouldnt worry about leaks, leak test it for 24 hours and use paper towels to spot leaks , sometimes you can get a bad fitting or one with damaged o ring, then a leak is possible.Do not overtighten fittings, its easy to strip grooves in acetal blocks.Some general advices now :) EK blocks come with Thermal pase, GELID EXTREME which is very good tim so there is no need to get extra tube.Also get another bottle of coolant. Remember to wash radiators many times to get the gunk out first.

From what I've read just now I'll probably use distilled water + an anti corossive for my entire loop.

Ah, I didn't even think about a large syringe, thanks for the tip. That should make it way easier. For a drain port I'd just use a T piece + a plug, right? Where would you put that in my system, directly after the second GPU? That seems to be the lowest point.

And lastly, should I go for smaller tubing? Do any of the bends look like they're too hard to do for a novice with 1/2 3/4 tubing?

Yes, its a good spot for drain port,between gpu 2 and 240 rad, but test if it works once you built the loop .I use acrylic hard tubing and used soft tubing only once so I cant give you any advice :(

If I had the funds currently available to do custom loop, I would do custom loop. No question about it XD

Watching a few more tutorials, apparently I'd also need (or want) a bleed port for the initial filling. Can I just use the fill-port on the reservoir or one of the ports on the very top of the radiator for that?

If you do not plan to use optical drive , you could use pressure membrane

with your tube routing I would use res fill port but dont run pump on top speed with that opened :D or dont`t fill res to max level straight away.Make sure pump doesnt suck air from res.

I think one of the last questions I have would be in regards to EK, from what I read all of their in-house stuff is very high quality, and they also seem to sell other high-quality components. I'm not too worried about spending maybe 50 bucks more because I bought it all at one place, I'm just worried about quality and longevity of my purchase here. Is there anything in my initial list that would be considered poor or mediocre in terms of quality? As long as that is not the case I think I'm more than ready and just need to think about whether I want to WC this current system or the next one.

If you plan to use anticorrosion +biocide or ready mix , there shouldnt be any problems. If you change to colored fluid there might be some stains.Some hoses tend to loose their looks as they can degrade, Just remember to wash radiators properly, till there is no debris in water, even premium radiators might have stuff left there

You can do it without pump ,but it takes a lot of shaking to release some stuff

I hate bumping my own threads like this, but I'd love to hear some more opinions on this whole thing before I pull the trigger on any of the components.
Just to clarify, I added a Y-splitter fitting + a plug to my list so I can use that as a drain port after the 90° adapter on the second GPU, I'll use distilled water + anti-corossion/biocide mix and besides that I think my original plan is the same.
My last few questions would be whether people would go for it with my current hardware (2 R9 290s and an i5 4670k), and whether any of the parts I choose are sub-par in terms of quality and reliability.

All I would change is making that back fan blow cold air to that triple rad so you aren't pushing heated air from the gpu rad to it. I would also do a parallel set up on that gpu fluid.

I also thought about the rear fan as an intake, that should guarantee positive air pressure in the case, feed the top rad fresh air and also provide some airflow over the mobo.
What exactly do you mean by a parallel setup for the GPUs, splitting the tube so it feeds both GPUs in parallel and then letting it flow back together to one tube after them? From what I've seen EK makes fairly low restriction blocks so that shouldn't be too much of an issue.

with valve

that makes a great combo for draining, you can use cheaper barrow fittings, they get positive reviews ,
place it at bottom card and you should have some room for draining system,if you decide to use back fan as intake remember to get dust filter for it

Consider doing something like this with your cards. That way both cards will get "cool" water instead of the second one getting the heated water from the first card.

That would just take 2 more fittings, but everything I've heard suggests that loop order makes absolutely no difference. That "hot" water from the first GPU is maybe a few °C warmer than the rest of the loop.
Have you done that yourself and seen significant improvements? Because as I said the vast majority of people say that it doesn't matter.

Well the second card in my system is used for it's not getting worked as hard...however I did notice a few degrees difference. I feel that it was worth the slight extra cost... When it's all about temps every little bit helps in my opinion.