My XSPC also leaked from one of the holes but I use plastic barbs , haha ... I fixed it by using a fatter O-Ring and so far its been good. You prob just got unlucky and I know how frustrating it is. 

Sorry to see you're having issues with the reservoir.  Might have to swing by the store for some Depends on your next run
 
My EK-RES X3 250 reservoir worked fine first time.
 
However, some of the ports require smaller than standard fittings. (they are step cut / counter-bored kind of deep for some unknown reason, standard fitting would bottom before it could seal the O-ring)
 
Are your reservoir ports not machined smooth or is the O-ring just not getting compressed ?
 
Let us know how it works out.

Scarlet-Tech
Zuhl, I am very sorry to hear that. Have you contacted customer support about it?

Can you get pictures of where the leaks are occurring and post them?

I have been in contact with EK support. Since this issue affects every port in the rear of the reservoir we have both concluded that the reservoir wasn't properly seated in the CRC when the threads were machined. EK has approved my RMA request and is sending me a replacement reservoir.
 

 

Scarlet-Tech
Hopefully the rma goes quick and you get back online. That is crazy that it keeps leaking.

They were nice enough to send me a replacement reservoir instead of having me send the old one back first. I don't even think they want the old one since I agreed to destroy it and send a photo of its remains. The other two fittings needed epoxy and sealant to keep them from leaking. I'll just have to swap out the pump which is working excellently. Hopefully I'll have it and be back up and running before the end of the week. I have the utmost confidence in EKWB and their parts. Truely a class act all around.

I ordered some compression fittings just for the back of the reservoir to make things easier. They do make fittings with shorter threads. The threads on this fitting are 2 to 3 threads shorter than the threads on my barb fittings: https://www.ekwb.com/shop/ek-csq-fitting-10-13mm-g1-4-nickel
 

Vlada011
That's my favorite fittings, 10/13mm Nickel... 
You should immediately to try compression fittings after first leak. 
Maybe they resolve problem. 
 

No, the fittings weren't the problem. Even the plug for the alternate input started dripping too. It dripped every few minutes after two days in service. It was fine and tight before that. I tightened a little more. No dice. I even replaced the O-ring. No dice. I tightened it a little more. It was so tight the threads were screaming for mercy. Coolant was seeping through the threads and past the O-ring. The threads were just cut at an angle preventing the O-ring from seating properly. Hopefully it's just this one reservoir affected. It is a new item and hopefully the whole batch isn't affected.

I just got the compression fittings by XSPC. Those things are a bear to get the hose on. No way those things will leak but if it's too much of a hassle I'll just use my barb fittings again. We shall see. I am looking forward to this and can't wait for my new res to arrive.

I feel your pain, Vlada011. If you weren't so darned far away I could give you a hand with some of my spare parts. The shipping cost alone would put me in the 'Poor House' plus the taxes, duties and import fees would kill us both.
 
I got bored and decided to install my Swiftech Maelstrom V2 again while waiting for my replacement EK reservoir. In order to insure proper troubleshooting and to be certain my workmanship was not to blame for the leaks and seepage I used the same type G1/4 barb fittings with the same black plactic ratchet style clamps I use throughout my loop. I ran for more than 1/2 hour without a single drop of coolant leaking. I shut down and waited another 1/2 hour and still bone dry. Satisfied my fittings or hoses weren't at fault I trimmed a little off of each hose just to give my new XSPC compression fittings a try. They seated perfectly but tightening the collar was a little more difficult than I anticipated. All is well and everything is purring along again. Now I just have to sit and wait for EKWB to send out my replacement reservoir. They informed me this morning they will get it to me ASAP. I can't wait to finally get a completely EK watercooling loop. EK customer support is being extremely understanding and helpful in this matter.
 

 

No leaks now. Now I can definitely say it was the reservoir and not me to blame for the leaks. I hope the replacement is perfect and doesn't give me the same problems. Hopefully I will have my new reservoir by this weekend or Monday at the latest. I trimmed these hoses to fit the EK reservoir perfectly and using the Swiftech unit makes the hose to my video board too long. It is almost hitting the fans on my upper radiator. At least it isn't leaking. It is a dry as an Egyptian Mummy right now. LOL

EVGATech_DaveB
Really surprising, but it happens, no one makes perfect stuff all the time.  But they are taking care of you and that's what is important.  At least the Swiftech one is moving along well.

The Swiftech Maelstrom V2 will make a nice backup in case of an emergency. EKWB is definitle taking care of me. My replacement res will arrive today some time and I can't wait to get started.

EK has been more than helpful with this issue. They sent me a replacement reservoir but it was only the shell. I had to swap everything over including face-plate, mounting grommets, baffle and plugs. Not a leak in sight. Not even a dribble. Thank you EKWB, you are the best. If it leaks now I have nobody to blame but myself. I'm not putting the side panels on yet or taking any pics until I am absolutely certain I am leak proof.

Cool GTX
Zuhl, good to see the progress and success with the new EK reservoir.
 
Keep dry my friend

I am so happy to finally have a completely EKWB custom loop unless you count the radiators. I am so worried right now it isn't funny. I only wish they would have included a T-10 bit tool or at least given me some warning about needing one. I had a T-10 screwdriver from one of my tool kits but having lost the feeling in my center two fingers of my right hand after my stroke made gripping it a hassle but I got it done. I know if I put the side panels on my case tonight it would invoke the curse of "Murphy's Law" and I would awake to a massive puddle under my PC.
 
I think I'll just sit here and admire the coolant flowing around while my nine 120 mm fans running at 100% whisper sweet nothings in my ear. LOL

Cool GTX
Still dry and motoring on ?

I had a few drops overnight yesterday. I couldn't understand where I went wrong so I ordered more fresh hose and more new compression fittings. It turns out it was the plug in the alternate return hose port. I tightened that as much as I could using that little Allen wrench tool that EK included in the kit. I am telling you it was really really tight and I tightened it before I put any other fittings or the pump on it so nothing interfered with turning it. I looked all day to see where those drops were coming from and couldn't see anything. I reached in there last night and felt some moisture around that plug with my fingers so I found my trusty tool with a variety of Allen Keys on it and got another 1/4 turn on it. Scared me because it made a creaking sound when I turned it. I was worried I was going to rip the threads out of the plastic. Anyway, I got up this morning and the paper towel under the reservoir was dry as a bone. Hooray!
 

EVGATech_DaveB
@ Zuhl
Glad to hear you running dry again!
 

After running all day I found two little green spots on the paper towel under the reservoir. Nothing major and only about the size of a nickel. I hope it was just some residue. Nothing at all after sitting all night. I will check again after I run it for the day. I have everything buttoned up and the side panels on the case so if it is only one drop per day I'm not going to get too worked up about it. I might just make that piece of paper towel a permanent fixture under the reservoir. I'm getting too old for this nonsense.