RO/DI flush kit ?

reefnetworth · 09/01/2008, 08:35 PM

how do they work?
which one is better?

TIA

Tc269 · 09/01/2008, 08:47 PM

They work by running water backwards thru the membrane this flushes out and larger particles blocking the membrane and prolongs the life of the membrane. I think they all work the same and can save lots of money in the long run.

reefnetworth · 09/01/2008, 08:59 PM

thanx, Tc269!

reefergeorge · 09/01/2008, 09:25 PM

Backwards, Really??
The ones I usually see just don't restrict the waste line.

AZDesertRat · 09/01/2008, 09:26 PM

No that is incorrect. All they do is run water around the exterior of the membrane at a higher velocity than the normal 4:1 waste ratio. They do not run water backwards through the membrane.
Flush kits have not been proven to do anyting at all. The problems are that once dissolved solids have been allowed to collect and solidify on the membranes surface no amount of flushing in the world will even break them up and move them out. For a flush kit to have any benefit whatsoever it must be used every time you shut the unit off starting with day one and forever from then on. If you have a RO membrane with an autoshutoff valve and float switch you do not know when the units starts and stops so its a waste of money. Large commercial systems get around this by using chemical treatments but small household systems are not set up for clean in place like that.
The best thing you can possible do is make darn sure your waste ratio is set at 4:1 and it stays there. Units that come with cartridge type fixed orfice flow restrictors are often not even close. Time your waste using a measuring cup and watch and if its not at 4:1 do yourself a favor and buy either a capillary tube type flow restrictor that you personally trim for an exact fit and flow or buy an adjsutable one and set the needle valve to 4:1 or both.

09/01/2008, 08:35 PM	#1
reefnetworth Premium Member Join Date: Mar 2006 Location: U.S.A. Posts: 3,810	RO/DI flush kit ? how do they work? which one is better? TIA __________________ GIVE A MAN A FISH, YOU FEED HIM FOR A DAY. TEACH A MAN TO FISH, HE FEEDS HIMSELF FOR LIFE. (NEVER, underestimate another man's greed) Current Tank Info: SPS dominated barebottom display with BB sump since 2005, most consistant parameters in 19+ years of reefkeeping.

09/01/2008, 08:47 PM	#2
Tc269 Registered Member Join Date: Feb 2008 Location: Wisconsin Posts: 615	They work by running water backwards thru the membrane this flushes out and larger particles blocking the membrane and prolongs the life of the membrane. I think they all work the same and can save lots of money in the long run. __________________ Want to See my Mini Build Click my little red house. Current Tank Info: 55gallon with 300watt MH 14K lights and a turbo flotor multi skimmer

09/01/2008, 08:59 PM	#3
reefnetworth Premium Member Join Date: Mar 2006 Location: U.S.A. Posts: 3,810	thanx, Tc269! __________________ GIVE A MAN A FISH, YOU FEED HIM FOR A DAY. TEACH A MAN TO FISH, HE FEEDS HIMSELF FOR LIFE. (NEVER, underestimate another man's greed) Current Tank Info: SPS dominated barebottom display with BB sump since 2005, most consistant parameters in 19+ years of reefkeeping.

09/01/2008, 09:25 PM	#4
reefergeorge Registered Member Join Date: Jun 2006 Location: St Louis MO Posts: 4,222	Backwards, Really?? The ones I usually see just don't restrict the waste line. __________________ $35-50 for a <1" frag of some stupid named thing that came from a colony you bought for $40-60 wholesale and chopped into 20-40 pieces? No thanks. "JasonH" Current Tank Info: 125 aggressive reef, DIY led lighting, swc cone skimmer, 33 gallon sump, posiden Ps3 return.

09/01/2008, 09:26 PM	#5
AZDesertRat Moved On Join Date: Jan 2002 Location: NW Phoenix Posts: 16,621	No that is incorrect. All they do is run water around the exterior of the membrane at a higher velocity than the normal 4:1 waste ratio. They do not run water backwards through the membrane. Flush kits have not been proven to do anyting at all. The problems are that once dissolved solids have been allowed to collect and solidify on the membranes surface no amount of flushing in the world will even break them up and move them out. For a flush kit to have any benefit whatsoever it must be used every time you shut the unit off starting with day one and forever from then on. If you have a RO membrane with an autoshutoff valve and float switch you do not know when the units starts and stops so its a waste of money. Large commercial systems get around this by using chemical treatments but small household systems are not set up for clean in place like that. The best thing you can possible do is make darn sure your waste ratio is set at 4:1 and it stays there. Units that come with cartridge type fixed orfice flow restrictors are often not even close. Time your waste using a measuring cup and watch and if its not at 4:1 do yourself a favor and buy either a capillary tube type flow restrictor that you personally trim for an exact fit and flow or buy an adjsutable one and set the needle valve to 4:1 or both.