multiple flow restrictors on RODI?

r6justin · 12/08/2018, 04:39 PM

i have a 75GPD RO membrane but have 450 and 300 flow restrictors and I believe I need a 550. I'm planning on getting the correct one ordered but looking for something as a quick fix as setting everything back up. Can I just run them both on the same line so i get more restriction or will it not doing anything?

Vinny Kreyling · 12/08/2018, 05:39 PM

Basically you are looking for a 4-1 ratio,
4 gallons of waste water for every gallon of product.
Whatever gets you there, you may have to settle getting close.

outssider · 12/08/2018, 06:16 PM

you can make yourself an adjustable flow restrictor very easily using parts from home depot....

manateemark · 12/08/2018, 07:20 PM

Quote:

Originally Posted by outssider

you can make yourself an adjustable flow restrictor very easily using parts from home depot....

Despite that not being on the product water line I would batik be hesitant to be using copper plumbing parts with anything that’s going to be near my tanks water due to possible corrosion issues.

otimer · 12/09/2018, 03:19 AM

The flow restrictors we can easily buy are not so accurate in their flow rating. I'm using a rodi 1/4" ball valve and adjust to get 3.5~4:1 ratio of waste and purified water.

12/08/2018, 04:39 PM	#1
r6justin Registered Member Join Date: Jul 2010 Location: Dublin, OH Posts: 165	multiple flow restrictors on RODI? i have a 75GPD RO membrane but have 450 and 300 flow restrictors and I believe I need a 550. I'm planning on getting the correct one ordered but looking for something as a quick fix as setting everything back up. Can I just run them both on the same line so i get more restriction or will it not doing anything?

12/08/2018, 05:39 PM	#2
Vinny Kreyling Registered Member Join Date: Nov 2002 Location: Miller Place, NY Posts: 7,206	Basically you are looking for a 4-1 ratio, 4 gallons of waste water for every gallon of product. Whatever gets you there, you may have to settle getting close. __________________ 250 gallon mixed reef, 2 Reefbreeder's Photon V 2, Deepwater BLDC 12, DAS EX-3 Skimmer, MTC mini cal, 2-3/4" Sea Swirls, Aquacontroller & 6 Tunze pumps.

12/09/2018, 03:19 AM	#5
otimer Registered Member Join Date: Jan 2016 Location: Seoul Korea Posts: 24	The flow restrictors we can easily buy are not so accurate in their flow rating. I'm using a rodi 1/4" ball valve and adjust to get 3.5~4:1 ratio of waste and purified water.