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pusanpa
01/27/2008, 11:57 PM
I have question regarding my RODI system.
Please have a look at the attached image.
My fellow reefer sent me this image showing RODI (with pressure tank) set up diagram.

http://i166.photobucket.com/albums/u113/pusanpa/r.jpg

My concern is from looking at this picture I found out that pressure tank is only used for RO water.
My Dual RODI uses pressure tank for both RO and RODI from the stored RO water in the pressure tank, then splitted to either RO faucet or DI cartrige for RODI water.
I think that in Normal RODI reef system, water pass through the DI cartridge very slowly with small amount of RO water.
I was worried of the water presure is too fast for the DI cartridge to purify.
If this is the problematic then I would use the pressure tank just for the drinking water. (IS check valve neccessary?)

I have algae problem in my reef tank and think this might be the cause.
Please let me know.

Chef Reef
01/28/2008, 12:10 AM
the pressure tank is for drinking water. thats all its for, there should be a hose attached to it that goes to a little metal spicket. and yea the check valve is neccessary as far as i know. are you just trying to find something to hold the water in?

silverwolf72
01/28/2008, 02:04 AM
I would think running your RO water threw your DI at the same rate it comes from the storage tank would no be sufficient for it to work properly.

qfrisco
01/28/2008, 02:05 PM
In this setup, turning on the DI faucet (pure water in the pic) will cause water to come from both the reservoir and the water supply. Water will then be deionized at that time. The DI filter should be able to keep up with the pressure from the tank - mine does.

The reservoir is probably 3-4 gallons. Once the reservoir is exhausted, the DI filter will be fed water directly from the RO membrane, which in turn is getting its water from the water supply.

Do you have a TDS meter? It would be good to check it. Water out of my reservoir comes out at 6-7 TDS, and after the DI filter it is 0 TDS, whether coming out of the reservoir or in realtime from the water supply.

AZDesertRat
01/28/2008, 02:15 PM
A good 10" vertical canister style DI filter with a tightly packed cartridge will work fine at the flow rates and pressures a bladder tank will produce. I would be hesitant to do it with a small low capacity horizontal filter though unless you can control the flow with a ball valve so its just a trickle. I store only RO water in my pressure tank and from there it feeds 3 different drinking faucets, an ice maker and my DI filters.

pusanpa
01/28/2008, 02:29 PM
Thanks a lot for help guys
.
My DI canister is smaller horizontal type.
So, I am leaning towards to AZDesertRat's idea of using valve to
reduce the water flow coming from the pressure tank.

Please let me know if you have any other comments.

http://i166.photobucket.com/albums/u113/pusanpa/ww.jpg

AZDesertRat
01/28/2008, 02:54 PM
One way to help the efficiency of the DI is to take it off the top of the membrane and mount it vertically next to the unit with the water entering from the bottom. By doing this you force the housing to stay full of water so all resin comes into contact with the water. When they are horizontal the housing may not fill completely so all resin does not get wet.

pusanpa
01/28/2008, 03:05 PM
"take it off the top of the membrane and mount it vertically next to the unit with the water entering from the bottom"

I will do that tonight. Thanks a lot AZDesertRat!