RO/DI booster pump?

[CNoonan]

Hey Guys..

I am ashamed to say that I have been doing aquarium maintenance for years, and have been buying water each and every time I do a water change on a customers aquarium.

I would already have an RO/DI unit, but was advised to wait until I found out more about my water pressure. I have well water, and I am pretty certain that water coming out of the sink I would like to use, would be around 25psi.
Now, we have obviously have enough water pressure to shower, run the dishwasher, and fill our inground pool up with the garden hose.. but I am told I would need atleast 45psi for the unit I was looking at (Melevs).

Is there anyway around a booster pump?

 

[marvik]

hi
you can add one before the entry point of the ro system and then you will do well to boost the pressure and also use a cut of valve to switch it on and off to turn pump automatic for not use a switch on and off

 

[ah30k]

RO performance (ie wasteroduction ratio) drops way off with low pressure. I have about 20psi at my house and ended up buying a booster pump for the RO/DI

I don't think there is any way around it.

 

[RokleM]

Yes, temp and pressure play a big role.

Buckeye Field Supply has a cool calculator on their site to show you how much it matters. I had ~40 PSI and cranked it up to ~85... HUUUUGE world of difference.

http://buckeyefieldsupply.com/calc.php

 

[Buckeye Hydro]

In your case, the booster pump is probably your best option. You can install your RODI system and then see what sort of pressure you have (assuming your RODI system comes with a pressure gauge.

With a well pump you'll find your water pressure swings from a low to a high pressure - 40 psi and 60 psi is a common setting on well pumps.

Russ

 

[zilofidelious]

Anyone know the ratio of waste/ro water to good RODI water? I can fill several buckets of RO water while the RODI is still cranking away on one bucket.

 

[ah30k]

4:1

 

[CNoonan]

Ok thanks guys.

I spoke with Marc from Melevs Reef and he's going to have something built for me. RO/DI with a booster pump, TDS meter, lots of neat stuff. I cannot wait to get it mounted on my wall and working.

 

[cabrego]

FWIW, I run my RODI system at about 25psi, and it works fine.


I am not using my rodi as efficient as I could sinc the efficiency is a function of operating pressure, but I still have 0tds.

What are you worried about? 45 psi is ideal, most of the membrane ratings are stated at particular psi and temp someting like 50 or 75 psi.

The psi will also effect your GPD too.

 

[RokleM]

Actually, most systems can be run much higher than 45, so "ideal" wouldn't be the correct word if you're going for greatest output. I think most of us wish to create the most amount of water quickly, with the least amount of waste, within our budget.

75gpd membrane, 65f, 25 PSI = 25gpd
75gpd membrane, 65f, 80 PSI = 101gpd

Additional blurb from BFS's site. Obviously your results and possibilities vary from vendor to vendor.

How much water pressure is needed to run an RO or RODI system?

The amount of pressure needed is dictated by the RO membrane. Factory specifications on our 50, 75, and 100 gpd systems call for at least 50 psi; and on our 150 gpd systems, 65 psi. You might get away with up to 10 psi less than these specifications, but be prepared for decreased performance in terms of how much water the membrane purifies, and how efficiently it performs.

We recommend not exceeding 90 psi. There are components in the systems with maximum operating pressures of 100 psi. At 90 psi you can expect exceptional performance from the membrane. If your line (plumbing) pressure exceeds 90 psi, install a pressure regulator (see www.buckeyefieldsupply.com) to reduce the pressure. If you would like to increase your line pressure (in 50, 75, and 100 gpd systems), install a booster pump.