Yup, best solution by far for those leaky DOS compression connectors... just make sure you use Teflon paste for the 1/8” threads.
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Is there a write up of how to do this and/or links to the connectors you used? TIA
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Yup, best solution by far for those leaky DOS compression connectors... just make sure you use Teflon paste for the 1/8” threads.
![]()
Is there a write up of how to do this and/or links to the connectors you used? TIA
www.freshwatersystems.com
Is there a write up of how to do this and/or links to the connectors you used? TIA
You will need 4 of these...
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John Guest Female Adapter NPTF Polypro - 1/4 x 1/8 NPTF
The John Guest female adapter makes connecting OD tubing to male NPT threads quick and easy. Manufactured in polypropylene with food grade EDPM O-ring, these fittings were developed for the filtered pure water market. Features: Push-fit Technology creates reliable, leak-free connections Used to...www.freshwatersystems.com
For instructions, click on the link in post #3 in this Neptune Forums discussion by the user Wiretech, who originally came up with this mod. Also note, I cut the nubs off my DOS tubing connectors and used a liberal amount of Teflon paste on the threads.
RO tubing to DOS connection
Hi, Has anyone seen an adapter that will connect standard 1/4" tubing used in RO applications to the larger tubing used on the DOS? Thanks, Dennisforum.neptunesystems.com
I plan on doing this mod when my DOS pumps come in. After I modify it can I just use regular 1/4" RO tubing to dose my trition elements?
Yup, that’s the purpose of installing these John Guest fittings... it’s so you can use the 1/4” OD RO tubing.

