RO/DI question

steved350 · 01/18/2009, 10:00 PM

I have a Whole house water softener with a carbon block currently installed in my house from Rain Soft. Can you guys make a suggestion as to what I should do about quality water for a reef setup? Also, what is the brand that I see people talk about that is selling on Ebay?

cmm1970 · 01/19/2009, 02:49 PM

Okay, the good news is that with the whole house softener and carbon block, you will at least be running your RO/DI unit with lower TDS water than lots of folks and that in turn will extend the life of your RO membrane dramatically.

That being said, you DO need a RO/DI unit to filter TDS=0 water for your reef tank. There are tons of ways to accomplish this goal, and there are others that will come in beneath me and criticize my recommendations. So here it goes...You can purchase the setup lots of places. The canisters most all use the 10" cartridge filters. You should look for a unit that does most if not all of these things:
1. Prefilter 1 micron will cause less line pressure drop than a 5 or 10 micron cartridge.
2. Carbon Bloc- .6 micron carbon blocs are available which would contribute less pressure drop through the prefilters than 1, 5, or 10 micron blocks. These two cartridges will prepare the water for interaction with the RO membrane.
3. RO Membrane-the Spectrapure 75GPD membranes are highly regarded, but you pay more $$$$ for them. You can find an excellent explanation as to why it might be important to pay up for this membrane in the Spectrapure forum here at Reef Central. They make a compelling case for use of a true 98% rejection rate membrane
4. DI chamber-The DI cartridge or cartridges should come after the RO membrane and filter only the RO water from the system. This will bring you from TDS=7-12 down to TDS=0.

So whether you buy an eBay unit or shoot your wad at Spectrapure, those are the basic elements that you would want for your unit.

Some good suppliers are:
Bulk Reef Supply (my favorite)
Buckeye Field SUpply
SPectrapure
Melev's Reef-He is a Reef Central dude
The FIlter Guys

So hope this helps, and for those that disagree, please be gentle in your critique.

Thanks,
Mike

HowardW · 01/20/2009, 09:23 AM

<<< Okay, the good news is that with the whole house softener and carbon block, you will at least be running your RO/DI unit with lower TDS water than lots of folks and that in turn will extend the life of your RO membrane dramatically. >>>

Actually a water softener will not lower the TDS of tap water and in some cases may actually raise TDS a bit.

cmm1970 · 01/20/2009, 11:39 AM

True about the water softener, but the carbon block is at least a 10 micron filter that will remove some TDS by the activity of the carbon block. So he most likely will still be in better shape as far as membrane mileage goes compared to completely untreated tap water.

Everyones Hero · 01/20/2009, 01:01 PM

I don't know about the eBay brands, but I know there are 3 RC sponsors that make quality units: BulkReefSupply.com, AirWaterIce.com, & TheFilterGuys.biz.

I have a unit made by The Filter Guys. It came pre-assembled & was making 0 TDS water within a few minutes. I think a user by the name of AZDesertRat (Only remember him because his avatar is of the guy from MAD magazine) swears by Bulk Reef Supply's system, especially since it's one of the cheapest complete filter systems you can find.

Arghhh · 01/20/2009, 02:14 PM

I have the 75GPD system from bulk reef supply. I was making 0 TDS water before the DI resin in about 30 seconds. Although my incoming TDS is only about 140 so your mileage may vary.

I have owned 3 other systems from ebay and I so far the bulk reef supply system had impressed me.

01/18/2009, 10:00 PM	#1
steved350 Registered Member Join Date: Jan 2009 Location: Houston Posts: 236	RO/DI question I have a Whole house water softener with a carbon block currently installed in my house from Rain Soft. Can you guys make a suggestion as to what I should do about quality water for a reef setup? Also, what is the brand that I see people talk about that is selling on Ebay? __________________ Don't let your kids Grow up to fast!!

01/20/2009, 09:23 AM	#3
HowardW Registered Member Join Date: Feb 2006 Location: Aurora, IL Posts: 1,763	<<< Okay, the good news is that with the whole house softener and carbon block, you will at least be running your RO/DI unit with lower TDS water than lots of folks and that in turn will extend the life of your RO membrane dramatically. >>> Actually a water softener will not lower the TDS of tap water and in some cases may actually raise TDS a bit. __________________ Florida live rock addict

01/19/2009, 02:49 PM	#2
cmm1970 Registered Member Join Date: Feb 2008 Location: Austin, TX Posts: 426	Okay, the good news is that with the whole house softener and carbon block, you will at least be running your RO/DI unit with lower TDS water than lots of folks and that in turn will extend the life of your RO membrane dramatically. That being said, you DO need a RO/DI unit to filter TDS=0 water for your reef tank. There are tons of ways to accomplish this goal, and there are others that will come in beneath me and criticize my recommendations. So here it goes...You can purchase the setup lots of places. The canisters most all use the 10" cartridge filters. You should look for a unit that does most if not all of these things: 1. Prefilter 1 micron will cause less line pressure drop than a 5 or 10 micron cartridge. 2. Carbon Bloc- .6 micron carbon blocs are available which would contribute less pressure drop through the prefilters than 1, 5, or 10 micron blocks. These two cartridges will prepare the water for interaction with the RO membrane. 3. RO Membrane-the Spectrapure 75GPD membranes are highly regarded, but you pay more $$$$ for them. You can find an excellent explanation as to why it might be important to pay up for this membrane in the Spectrapure forum here at Reef Central. They make a compelling case for use of a true 98% rejection rate membrane 4. DI chamber-The DI cartridge or cartridges should come after the RO membrane and filter only the RO water from the system. This will bring you from TDS=7-12 down to TDS=0. So whether you buy an eBay unit or shoot your wad at Spectrapure, those are the basic elements that you would want for your unit. Some good suppliers are: Bulk Reef Supply (my favorite) Buckeye Field SUpply SPectrapure Melev's Reef-He is a Reef Central dude The FIlter Guys So hope this helps, and for those that disagree, please be gentle in your critique. Thanks, Mike

01/20/2009, 11:39 AM	#4
cmm1970 Registered Member Join Date: Feb 2008 Location: Austin, TX Posts: 426	True about the water softener, but the carbon block is at least a 10 micron filter that will remove some TDS by the activity of the carbon block. So he most likely will still be in better shape as far as membrane mileage goes compared to completely untreated tap water.

01/20/2009, 01:01 PM	#5
Everyones Hero Registered Member. Join Date: Jun 2008 Location: Leonardtown, MD Posts: 1,154	I don't know about the eBay brands, but I know there are 3 RC sponsors that make quality units: BulkReefSupply.com, AirWaterIce.com, & TheFilterGuys.biz. I have a unit made by The Filter Guys. It came pre-assembled & was making 0 TDS water within a few minutes. I think a user by the name of AZDesertRat (Only remember him because his avatar is of the guy from MAD magazine) swears by Bulk Reef Supply's system, especially since it's one of the cheapest complete filter systems you can find.

01/20/2009, 02:14 PM	#6
Arghhh Registered Member Join Date: Jan 2009 Location: Olympia, WA Posts: 16	I have the 75GPD system from bulk reef supply. I was making 0 TDS water before the DI resin in about 30 seconds. Although my incoming TDS is only about 140 so your mileage may vary. I have owned 3 other systems from ebay and I so far the bulk reef supply system had impressed me.