DOS tubing not fitting.

HandsyLobster · Apr 10, 2024

Hi All,

So I have 2 DOS pumps and got RO tubing for it 1/4" and this tubing keeps sliding out of the end cap. Ive seen these parts on a few other DOS pumps and seems like people are using those to keep there RO tubing connected and its also at a 90 DEG angle.

Any help would be awesome.

Thanks!

areefer01 · Apr 10, 2024

You could try warming some water, soaking the RO tubing for a bit, then attach it. You mentioned end caps so I am guessing the John Guest adapters? I have two DOS units and have them on both. Not the 90 elbow but standard fittings. The work great and are a good quality of life improvement.

Neptune DOS fittings

Hi all, Just watched a recent Reefbuilder video of his tour of Top Shelf Aquatics and loved how clean his DOS systems looked due to their modified outlets. I will attach a photo of what I am looking at. I have circled in red the fittings I am looking to source if possible here in the UK. Any...

www.reef2reef.com

HandsyLobster · Apr 10, 2024

Thank you so much im going to go with the John Guest Adapters. Do I just get the 1/4" because im a little confused how they screw in?

areefer01 · Apr 11, 2024

I will have to see if I can find the thread on the Neptune forums as I don't have it handy, sorry. A search like "Neptune dos john guest fittings" may find it though. I went with the John Guest fittings 1/4" tube x 1/8" female nptf. I bought the bulk package because I have two DOS units and wanted spares.

Basically you are removing the current fittings, trimming off the cone/nipples with a razor (be careful and go slow), then screw on the new John Guest fittings and you are done. Some people used a bit of teflon tape.

Note: if you do not remove the cone/nipple the tube will not seat all the way into the John Guest fitting.
https://forum.neptunesystems.com/newreply.php?do=newreply&p=172701&noquote=1
I removed one of my DOS units and the fitting so you could get an example/idea. Not sure if that helps.